Ubuntu Security Advisories

Calum Hutton discovered that rsync contained a heap-based out-of-bounds read when handling file transfers. A remote attacker with read access to an rsync server could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, and Ubuntu 25.10. (CVE-2025-10158) Batuhan Sancak, Damien Neil, and Michael Stapelberg discovered that rsync daemons configured without chroot protection were exposed to a race condition on parent path components. A local attacker with write access to a module could possibly use this issue to overwrite files, obtain sensitive information, or escalate privileges. (CVE-2026-29518) It was discovered that rsync did not properly validate a length value while sorting extended attributes. An attacker could possibly use this issue to cause a denial of service. (CVE-2026-41035) It was discovered that rsync performed reverse-DNS lookups after chrooting in some daemon configurations. A remote attacker could possibly use this issue to bypass hostname-based access controls and access network services. (CVE-2026-43617) Omar Elsayed discovered that rsync did not properly check for integer overflows while decoding compressed tokens. A remote attacker could possibly use this issue to obtain sensitive information. (CVE-2026-43618) Andrew Tridgell discovered that rsync did not fully fix a symlink race condition in path-based system calls for daemons configured without chroot protection. A local attacker could possibly use this issue to overwrite files, obtain sensitive information, or escalate privileges. (CVE-2026-43619) Pratham Gupta discovered that rsync did not properly validate an index while processing file lists. A remote attacker could possibly use this issue to cause rsync to crash, resulting in a denial of service. (CVE-2026-43620) Michal Ruprich discovered that rsync contained an off-by-one error while handling HTTP proxy responses. An attacker able to intercept network communications or a malicious proxy server could possibly use this issue to cause a denial of service. (CVE-2026-45232)

Andrew Griffiths discovered that Unbound did not properly handle certain DNSCrypt packets. A remote attacker could possibly use this issue to cause Unbound to crash, resulting in a denial of service. (CVE-2026-32792) Qifan Zhang discovered that Unbound incorrectly handled DNSSEC validation in certain situations. A remote attacker could possibly use this issue to execute arbitrary code. This issue only affected Ubuntu 24.04 LTS, Ubuntu 25.10, and Ubuntu 26.04 LTS. (CVE-2026-33278) Qifan Zhang discovered that Unbound incorrectly handled certain ghost domain name records. A remote attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 24.04 LTS, Ubuntu 25.10, and Ubuntu 26.04 LTS. (CVE-2026-40622) Qifan Zhang discovered that Unbound did not properly limit processing of long EDNS option lists. A remote attacker could possibly use this issue to cause Unbound to use excessive resources, leading to a denial of service. (CVE-2026-41292) Qifan Zhang discovered that Unbound incorrectly handled jostle logic under certain circumstances. A remote attacker could possibly use this issue to cause Unbound to use excessive resources, leading to a denial of service. (CVE-2026-42534) Qifan Zhang discovered that Unbound did not properly bound NSEC3 hash calculations. A remote attacker could possibly use this issue to cause Unbound to use excessive resources, leading to a denial of service. (CVE-2026-42923) Qifan Zhang discovered that Unbound incorrectly handled multiple EDNS options in certain situations. A remote attacker could possibly use this issue to cause Unbound to crash, resulting in a denial of service, or execute arbitrary code. This issue only affected Ubuntu 24.04 LTS, Ubuntu 25.10, and Ubuntu 26.04 LTS. (CVE-2026-42944) Qifan Zhang discovered that Unbound incorrectly handled DNSSEC validation of malicious content. A remote attacker could possibly use this issue to cause Unbound to crash, resulting in a denial of service. (CVE-2026-42959) TaoFei Guo, Yang Luo, and JianJun Chen discovered that Unbound incorrectly handled delegation processing in certain situations. A remote attacker could possibly use this issue to poison the DNS cache and obtain sensitive information. (CVE-2026-42960) Qifan Zhang discovered that Unbound did not properly bound name compression in certain cases. A remote attacker could possibly use this issue to cause Unbound to use excessive resources, leading to a denial of service. (CVE-2026-44390) Qifan Zhang discovered that Unbound had a use-after-free issue in RPZ handling. A remote attacker could possibly use this issue to cause Unbound to crash, resulting in a denial of service, or execute arbitrary code. This issue only affected Ubuntu 24.04 LTS, Ubuntu 25.10, and Ubuntu 26.04 LTS. (CVE-2026-44608)

It was discovered that the Linux kernel algif_aead module did not properly handle in-place cryptographic operations. This flaw is known as Copy Fail. A local attacker could use this to escalate privileges, or possibly escape a container. (CVE-2026-31431) Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: - Cryptographic API; - Packet sockets; (CVE-2026-31504, CVE-2026-43033, CVE-2026-43077, CVE-2026-43078)

It was discovered that the Linux kernel algif_aead module did not properly handle in-place cryptographic operations. This flaw is known as Copy Fail. A local attacker could use this to escalate privileges, or possibly escape a container. (CVE-2026-31431) Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: - Cryptographic API; - Packet sockets; - TLS protocol; (CVE-2026-31504, CVE-2026-31533, CVE-2026-43033, CVE-2026-43077, CVE-2026-43078)

It was discovered that the Linux kernel algif_aead module did not properly handle in-place cryptographic operations. This flaw is known as Copy Fail. A local attacker could use this to escalate privileges, or possibly escape a container. (CVE-2026-31431) Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: - Cryptographic API; - Ethernet bonding driver; - SMB network file system; - Netfilter; - io_uring subsystem; - Packet sockets; - TLS protocol; (CVE-2024-35862, CVE-2024-50060, CVE-2026-23274, CVE-2026-23351, CVE-2026-31419, CVE-2026-31504, CVE-2026-31533, CVE-2026-43033, CVE-2026-43077, CVE-2026-43078)

It was discovered that the Linux kernel algif_aead module did not properly handle in-place cryptographic operations. This flaw is known as Copy Fail. A local attacker could use this to escalate privileges, or possibly escape a container. (CVE-2026-31431) Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: - ARM64 architecture; - x86 architecture; - Cryptographic API; - Compute Acceleration Framework; - Drivers core; - Null block device driver; - Ublk userspace block driver; - Bluetooth drivers; - Counter interface drivers; - DMA engine subsystem; - DPLL subsystem; - GPU drivers; - HID subsystem; - Intel Trace Hub HW tracing drivers; - IIO ADC drivers; - IIO subsystem; - On-Chip Interconnect management framework; - IRQ chip drivers; - Modular ISDN driver; - LED subsystem; - Multiple devices driver; - UACCE accelerator framework; - MMC subsystem; - Ethernet bonding driver; - Network drivers; - Mellanox network drivers; - NVME drivers; - PHY drivers; - x86 platform drivers; - i.MX PM domains; - SCSI subsystem; - SLIMbus drivers; - SPI subsystem; - TCM subsystem; - W1 Dallas's 1-wire bus driver; - Xen hypervisor drivers; - BTRFS file system; - EFI Variable file system; - exFAT file system; - Ext4 file system; - HFS+ file system; - Network file system (NFS) client; - Network file system (NFS) server daemon; - NTFS3 file system; - SMB network file system; - Scheduler infrastructure; - Netfilter; - NFC subsystem; - Tracing infrastructure; - io_uring subsystem; - BPF subsystem; - Perf events; - Floating proportions library; - Memory management; - Bluetooth subsystem; - CAN network layer; - Ceph Core library; - Networking core; - IPv4 networking; - IPv6 networking; - L2TP protocol; - MAC80211 subsystem; - NET/ROM layer; - Packet sockets; - Network traffic control; - SCTP protocol; - TLS protocol; - Unix domain sockets; - VMware vSockets driver; - Wireless networking; - ALSA AC97 driver; - Generic PCM loopback sound driver; - Creative Sound Blaster X-Fi driver; - AMD SoC Alsa drivers; - Texas InstrumentS Audio (ASoC/HDA) drivers; - USB sound devices; - KVM subsystem; (CVE-2024-50004, CVE-2024-58096, CVE-2024-58097, CVE-2025-37926, CVE-2025-38201, CVE-2025-38591, CVE-2025-40039, CVE-2025-40082, CVE-2025-40149, CVE-2025-68351, CVE-2025-68358, CVE-2025-68365, CVE-2025-68725, CVE-2025-68749, CVE-2025-68803, CVE-2025-68823, CVE-2025-71160, CVE-2025-71162, CVE-2025-71163, CVE-2025-71180, CVE-2025-71182, CVE-2025-71183, CVE-2025-71184, CVE-2025-71185, CVE-2025-71186, CVE-2025-71188, CVE-2025-71189, CVE-2025-71190, CVE-2025-71191, CVE-2025-71192, CVE-2025-71193, CVE-2025-71194, CVE-2025-71195, CVE-2025-71196, CVE-2025-71197, CVE-2025-71198, CVE-2025-71199, CVE-2025-71200, CVE-2025-71220, CVE-2025-71222, CVE-2025-71224, CVE-2025-71225, CVE-2025-71268, CVE-2026-22976, CVE-2026-22977, CVE-2026-22978, CVE-2026-22979, CVE-2026-22980, CVE-2026-22982, CVE-2026-22984, CVE-2026-22990, CVE-2026-22991, CVE-2026-22992, CVE-2026-22994, CVE-2026-22996, CVE-2026-22997, CVE-2026-22998, CVE-2026-22999, CVE-2026-23000, CVE-2026-23001, CVE-2026-23003, CVE-2026-23005, CVE-2026-23006, CVE-2026-23010, CVE-2026-23011, CVE-2026-23019, CVE-2026-23020, CVE-2026-23021, CVE-2026-23025, CVE-2026-23026, CVE-2026-23030, CVE-2026-23031, CVE-2026-23032, CVE-2026-23033, CVE-2026-23035, CVE-2026-23037, CVE-2026-23038, CVE-2026-23047, CVE-2026-23049, CVE-2026-23050, CVE-2026-23053, CVE-2026-23054, CVE-2026-23056, CVE-2026-23057, CVE-2026-23058, CVE-2026-23059, CVE-2026-23061, CVE-2026-23062, CVE-2026-23063, CVE-2026-23064, CVE-2026-23065, CVE-2026-23068, CVE-2026-23069, CVE-2026-23071, CVE-2026-23073, CVE-2026-23075, CVE-2026-23076, CVE-2026-23078, CVE-2026-23080, CVE-2026-23083, CVE-2026-23084, CVE-2026-23085, CVE-2026-23086, CVE-2026-23087, CVE-2026-23088, CVE-2026-23089, CVE-2026-23090, CVE-2026-23091, CVE-2026-23093, CVE-2026-23094, CVE-2026-23095, CVE-2026-23096, CVE-2026-23097, CVE-2026-23098, CVE-2026-23099, CVE-2026-23101, CVE-2026-23102, CVE-2026-23103, CVE-2026-23105, CVE-2026-23107, CVE-2026-23108, CVE-2026-23110, CVE-2026-23113, CVE-2026-23116, CVE-2026-23119, CVE-2026-23120, CVE-2026-23121, CVE-2026-23123, CVE-2026-23124, CVE-2026-23125, CVE-2026-23126, CVE-2026-23128, CVE-2026-23129, CVE-2026-23131, CVE-2026-23133, CVE-2026-23135, CVE-2026-23136, CVE-2026-23139, CVE-2026-23140, CVE-2026-23141, CVE-2026-23142, CVE-2026-23144, CVE-2026-23145, CVE-2026-23146, CVE-2026-23148, CVE-2026-23150, CVE-2026-23151, CVE-2026-23156, CVE-2026-23159, CVE-2026-23160, CVE-2026-23163, CVE-2026-23164, CVE-2026-23166, CVE-2026-23167, CVE-2026-23168, CVE-2026-23170, CVE-2026-23172, CVE-2026-23173, CVE-2026-23176, CVE-2026-23178, CVE-2026-23179, CVE-2026-23180, CVE-2026-23182, CVE-2026-23187, CVE-2026-23190, CVE-2026-23191, CVE-2026-23193, CVE-2026-23198, CVE-2026-23200, CVE-2026-23202, CVE-2026-23204, CVE-2026-23205, CVE-2026-23206, CVE-2026-23212, CVE-2026-23213, CVE-2026-23214, CVE-2026-23215, CVE-2026-23216, CVE-2026-23254, CVE-2026-23256, CVE-2026-23257, CVE-2026-23258, CVE-2026-23260, CVE-2026-23261, CVE-2026-23262, CVE-2026-23264, CVE-2026-23274, CVE-2026-23351, CVE-2026-23394, CVE-2026-31419, CVE-2026-31504, CVE-2026-31533, CVE-2026-43033, CVE-2026-43077, CVE-2026-43078)

It was discovered that the Linux kernel algif_aead module did not properly handle in-place cryptographic operations. This flaw is known as Copy Fail. A local attacker could use this to escalate privileges, or possibly escape a container. (CVE-2026-31431) Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: - S390 architecture; - Cryptographic API; - GPU drivers; - Ethernet bonding driver; - Network file system (NFS) server daemon; - Distributed Switch Architecture; - Netfilter; - Control group (cgroup); - Kernel kexec() syscall; - Memory management; - MAC80211 subsystem; - Multipath TCP; - Packet sockets; - TLS protocol; - Unix domain sockets; (CVE-2025-71088, CVE-2025-71090, CVE-2025-71127, CVE-2025-71134, CVE-2025-71139, CVE-2025-71141, CVE-2025-71142, CVE-2025-71144, CVE-2025-71152, CVE-2025-71155, CVE-2026-23274, CVE-2026-23351, CVE-2026-23394, CVE-2026-31419, CVE-2026-31504, CVE-2026-31533, CVE-2026-43033, CVE-2026-43077, CVE-2026-43078)

It was discovered that Highlight.js used plain JavaScript objects for internal language name lookups, making them susceptible to prototype pollution attacks. An attacker could use this to cause a denial of service or unexpected application behaviour.

Stonejiajia, Shir Tamari and Sagi Tzadik discovered that the OverlayFS implementation in the Ubuntu Linux kernel did not properly perform permission checks in certain situations. A local attacker could possibly use this to gain elevated privileges. (CVE-2023-2640) Shir Tamari and Sagi Tzadik discovered that the OverlayFS implementation in the Ubuntu Linux kernel did not properly perform permission checks in certain situations. A local attacker could possibly use this to gain elevated privileges. (CVE-2023-32629) Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: - ARM64 architecture; - Block layer subsystem; - Drivers core; - Bluetooth drivers; - DMA engine subsystem; - GPU drivers; - HID subsystem; - Intel Trace Hub HW tracing drivers; - IIO ADC drivers; - IRQ chip drivers; - Modular ISDN driver; - LED subsystem; - UACCE accelerator framework; - Ethernet bonding driver; - Network drivers; - STMicroelectronics network drivers; - Ethernet team driver; - NVME drivers; - PHY drivers; - SLIMbus drivers; - W1 Dallas's 1-wire bus driver; - Xen hypervisor drivers; - BTRFS file system; - Ext4 file system; - Network file system (NFS) client; - Network file system (NFS) server daemon; - NTFS3 file system; - SMB network file system; - NFC subsystem; - BPF subsystem; - IRQ subsystem; - Memory management; - Bluetooth subsystem; - CAN network layer; - Networking core; - IPv4 networking; - IPv6 networking; - L2TP protocol; - NET/ROM layer; - Network traffic control; - SCTP protocol; - TLS protocol; - XFRM subsystem; - Creative Sound Blaster X-Fi driver; - USB sound devices; (CVE-2023-53421, CVE-2023-53520, CVE-2023-53662, CVE-2023-54207, CVE-2025-38057, CVE-2025-38125, CVE-2025-38232, CVE-2025-38408, CVE-2025-38591, CVE-2025-40149, CVE-2025-40164, CVE-2025-68211, CVE-2025-68340, CVE-2025-68365, CVE-2025-68725, CVE-2025-68817, CVE-2025-71162, CVE-2025-71163, CVE-2025-71185, CVE-2025-71186, CVE-2025-71188, CVE-2025-71190, CVE-2025-71191, CVE-2025-71194, CVE-2025-71196, CVE-2025-71197, CVE-2025-71199, CVE-2026-22997, CVE-2026-22998, CVE-2026-22999, CVE-2026-23001, CVE-2026-23003, CVE-2026-23011, CVE-2026-23026, CVE-2026-23033, CVE-2026-23037, CVE-2026-23038, CVE-2026-23049, CVE-2026-23056, CVE-2026-23058, CVE-2026-23061, CVE-2026-23063, CVE-2026-23064, CVE-2026-23071, CVE-2026-23073, CVE-2026-23075, CVE-2026-23076, CVE-2026-23078, CVE-2026-23080, CVE-2026-23083, CVE-2026-23084, CVE-2026-23085, CVE-2026-23087, CVE-2026-23089, CVE-2026-23090, CVE-2026-23091, CVE-2026-23093, CVE-2026-23095, CVE-2026-23096, CVE-2026-23097, CVE-2026-23098, CVE-2026-23099, CVE-2026-23101, CVE-2026-23103, CVE-2026-23105, CVE-2026-23108, CVE-2026-23112, CVE-2026-23119, CVE-2026-23120, CVE-2026-23121, CVE-2026-23124, CVE-2026-23125, CVE-2026-23128, CVE-2026-23133, CVE-2026-23145, CVE-2026-23146, CVE-2026-23150, CVE-2026-23164, CVE-2026-23167, CVE-2026-23170, CVE-2026-23209, CVE-2026-23273)

Stonejiajia, Shir Tamari and Sagi Tzadik discovered that the OverlayFS implementation in the Ubuntu Linux kernel did not properly perform permission checks in certain situations. A local attacker could possibly use this to gain elevated privileges. (CVE-2023-2640) Shir Tamari and Sagi Tzadik discovered that the OverlayFS implementation in the Ubuntu Linux kernel did not properly perform permission checks in certain situations. A local attacker could possibly use this to gain elevated privileges. (CVE-2023-32629) Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: - Network drivers; - NVME drivers; (CVE-2026-23112, CVE-2026-23273)

Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: - Network drivers; - NVME drivers; - Netfilter; (CVE-2026-23112, CVE-2026-23231, CVE-2026-23273)

Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: - Network drivers; - BTRFS file system; - Sun RPC protocol; - XFRM subsystem; (CVE-2022-49033, CVE-2024-27388, CVE-2024-49938, CVE-2024-50008, CVE-2024-50142)

Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: - Network drivers; - NVME drivers; - IPv4 networking; (CVE-2024-50304, CVE-2026-23112, CVE-2026-23209)

Takuya Aramaki discovered that Smarty did not properly escape JavaScript code. An attacker could possibly use this issue to conduct a cross-site scripting attack.

It was discovered that the nginx ngx_http_rewrite_module component incorrectly handled certain rewrite directives. A remote attacker could use this issue to cause nginx to crash, resulting in a denial of service, or possibly execute arbitrary code.

It is discovered that Avahi incorrectly handled crafted input. A remote attacker could possibly use this issue to crash the program, resulting in a denial of service. This issue only affected Ubuntu 14.04 LTS, Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, Ubuntu 22.04 LTS and Ubuntu 24.04 LTS. (CVE-2026-24401) Guillaume Meunier discovered that Avahi incorrectly handled crafted input. An attacker could possibly use this issue to crash the program, resulting in a denial of service. (CVE-2026-34933)

It was discovered that Exim incorrectly handled BDAT body parsing. A remote attacker could use this issue to cause Exim to crash, resulting in a denial of service, or possibly execute arbitrary code.

Andrew S. Fasano, Royce M, and Hugo Martinez Ray discovered that Dnsmasq did not allocate the necessary space to store domain names in some contexts. An attacker could possibly use this issue to write out-of-bounds, and could cause a denial of service or execute arbitrary code. (CVE-2026-2291) Royce M discovered that Dnsmasq could loop infinitely due to erroneously missing the window header. An attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, Ubuntu 25.10, and Ubuntu 26.04 LTS. (CVE-2026-4890) Royce M discovered that a maliciously crafted packet could cause Dnsmasq to report a negative length. An attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, Ubuntu 25.10, and Ubuntu 26.04 LTS. (CVE-2026-4891) Royce M and Asim Viladi Oglu Manizada discovered that certain configurations of Dnsmasq could write over the DHCPv6 CLID buffer within a privileged helper. An attacker could possibly use this issue to cause a denial of service or execute arbitrary code. (CVE-2026-4892) Royce M discovered that certain configurations of Dnsmasq could bypass internal bounds checks. An attacker could possibly use this issue to permit malformed packets, and could cause a denial of service. (CVE-2026-4893) Hugo Martinez discovered that Dnsmasq did not check the rdlen element of a record. An attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, Ubuntu 25.10, and Ubuntu 26.04 LTS. (CVE-2026-5172)

Qualys discovered that several vulnerabilities existed in the AppArmor Linux kernel Security Module (LSM). An unprivileged local attacker could use these issues to load, replace, and remove arbitrary AppArmor profiles causing denial of service, exposure of sensitive information (kernel memory), local privilege escalation, or possibly escape a container. (LP: #2143853, CVE-2026-23268, CVE-2026-23269, CVE-2026-23403, CVE-2026-23404, CVE-2026-23405, CVE-2026-23410, CVE-2026-23411) Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: - ARM64 architecture; - Cryptographic API; - GPU drivers; - Network drivers; - UDF file system; - NFC subsystem; - Network traffic control; - Sun RPC protocol; - XFRM subsystem; (CVE-2024-27388, CVE-2024-46777, CVE-2024-46816, CVE-2024-49938, CVE-2024-50008, CVE-2024-50142, CVE-2025-21735, CVE-2025-37849, CVE-2026-23060, CVE-2026-23074, CVE-2026-23209)

Qualys discovered that several vulnerabilities existed in the AppArmor Linux kernel Security Module (LSM). An unprivileged local attacker could use these issues to load, replace, and remove arbitrary AppArmor profiles causing denial of service, exposure of sensitive information (kernel memory), local privilege escalation, or possibly escape a container. (LP: #2143853, CVE-2026-23268, CVE-2026-23269, CVE-2026-23403, CVE-2026-23404, CVE-2026-23405, CVE-2026-23410, CVE-2026-23411) Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: - GPU drivers; - Network drivers; - Sun RPC protocol; - XFRM subsystem; (CVE-2024-27388, CVE-2024-46816, CVE-2024-49938, CVE-2024-50008, CVE-2024-50142, CVE-2026-23209)