Ubuntu Security Advisories

Jared Deckard discovered that Python marshmallow did not correctly handle hiding certain fields. An attacker could possibly use this issue to leak sensitive information. This issue only affected Ubuntu 18.04 LTS. (CVE-2018-17175) It was discovered that Python marshmallow did not efficiently handle merging certain objects. An attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, Ubuntu 24.04 LTS and Ubuntu 26.04 LTS. (CVE-2025-68480)

It was discovered that Roundcube Webmail mishandled Punycode xn-- domain names. An attacker could possibly use this issue to cause a homograph attack. (CVE-2019-15237) It was discovered that Roundcube Webmail did not properly sanitize certain attributes when handling CSS within HTML messages and certain SVG attributes. An attacker could possibly use this issue to cause a cross-site scripting attack. (CVE-2024-38356, CVE-2024-38357) It was discovered that Roundcube Webmail did not properly sanitize certain HTML attributes when rendering e-mail messages. An attacker could possibly use this issue to cause a cross-site scripting attack. (CVE-2024-42008) It was discovered that Roundcube Webmail did not properly filter certain CSS token sequences within rendered e-mail messages. An attacker could possibly use this issue to obtain sensitive information. (CVE-2024-42010) It was discovered that Roundcube Webmail did not properly treat an SVG tag as an image source within its HTML sanitizer. An attacker could possibly use this issue to bypass remote image blocking to track email open actions or potentially bypass access control. (CVE-2026-25916) It was discovered that Roundcube Webmail did not properly handle comments within Cascading Style Sheets (CSS). An attacker could possibly use this issue to perform a CSS injection attack. (CVE-2026-26079)

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-2026-23406, CVE-2026-23407, CVE-2026-23408, CVE-2026-23409, 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; - x86 architecture; - Cryptographic API; - GPU drivers; - I2C subsystem; - BTRFS file system; - XFRM subsystem; - Padata parallel execution mechanism; - IPv4 networking; - IPv6 networking; - MAC80211 subsystem; - Netfilter; - Network traffic control; - SMC sockets; (CVE-2021-47599, CVE-2022-48875, CVE-2022-49046, CVE-2022-49698, CVE-2024-46816, CVE-2024-49927, CVE-2024-56640, CVE-2025-21726, CVE-2025-21780, CVE-2025-37849, CVE-2025-40019, CVE-2025-40215, CVE-2026-23060, CVE-2026-23074)

Christos Papakonstantinou discovered that the OpenSSH scp tool incorrectly handled the legacy scp protocol (-O) option. This could result in certain files being installed setuid or setgid, contrary to expectations. (CVE-2026-35385) Florian Kohnhäuser discovered that OpenSSH incorrectly handled shell metacharacters in usernames within a command line. When untrusted usernames and non-default configurations using % in ssh_config are being used, an attacker could possibly use this issue to execute arbitrary code. (CVE-2026-35386) Christos Papakonstantinou discovered that OpenSSH incorrectly handled parsing the PubkeyAcceptedAlgorithms and HostbasedAcceptedAlgorithms options. This could result in unintended ECDSA algorithms being used, contrary to expectations. (CVE-2026-35387) Michalis Vasileiadis discovered that OpenSSH incorrectly handled proxy-mode multiplexing sessions. This could result in no confirmation being asked, contrary to expectations. (CVE-2026-35388) Vladimir Tokarev discovered that OpenSSH incorrectly handled certificates with the principal name containing a comma character when using user-trusted CA keys in authorized_keys and an authorized_keys principals="" option that lists more than one principal. This could result in inappropriate principal matching, contrary to expectations. (CVE-2026-35414)

USN-8195-1 fixed a vulnerability in PackageKit. This update provides the corresponding fix to Ubuntu 16.04 LTS, Ubuntu 18.04 LTS and Ubuntu 20.04 LTS. Original advisory details: It was discovered that PackageKit incorrectly handled certain transactions. A local attacker could use this issue to install arbitrary packages as root, possibly resulting in privilege escalation.

It was discovered that wheel did not correctly handle certain file paths. If a user or automated system were tricked into opening a specially crafted file, an attacker could possibly use this issue to execute arbitrary code.

USN-8198-1 fixed vulnerabilities in Tornado. This update provides the corresponding updates for Ubuntu 26.04 LTS. Original advisory details: It was discovered that Tornado incorrectly handled parsing of large multipart request bodies. An attacker could possibly use this issue to cause a denial of service. (CVE-2026-31958) It was discovered that Tornado did not properly validate characters in cookie values. An attacker could possibly use this issue to inject arbitrary cookie attributes. (CVE-2026-35536)

Cameron Criswell discovered that UltraJSON contained a memory leak that would occur when parsing large integers. An attacker could possibly use this issue to cause UltraJSON to crash, resulting in a denial of service. This issue only affected Ubuntu 24.04 LTS, Ubuntu 25.10, and Ubuntu 26.04 LTS. (CVE-2026-32874) It was discovered that UltraJSON contained integer overflow/underflow issues when calculating how much memory to reserve for indentation in certain instances. An attacker could possibly use this issue to cause UltraJSON to crash, resulting in a denial of service. (CVE-2026-32875)

Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo Rizzo discovered that some AMD Zen processors did not properly verify the signature of CPU microcode. This flaw is known as EntrySign. A privileged attacker could possibly use this issue to cause load malicious CPU microcode causing loss of integrity and confidentiality. (CVE-2024-36347) 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: - MIPS architecture; - PowerPC architecture; - x86 architecture; - Block layer subsystem; - Cryptographic API; - ACPI drivers; - Network block device driver; - Bluetooth drivers; - Character device driver; - TPM device driver; - Clock framework and drivers; - Data acquisition framework and drivers; - Hardware crypto device drivers; - GPU drivers; - Hardware monitoring drivers; - InfiniBand drivers; - Input Device core drivers; - IOMMU subsystem; - IRQ chip drivers; - Macintosh device drivers; - Multiple devices driver; - Media drivers; - Network drivers; - Mellanox network drivers; - STMicroelectronics network drivers; - Ethernet team driver; - MediaTek network drivers; - NVME drivers; - PA-RISC drivers; - Chrome hardware platform drivers; - x86 platform drivers; - Voltage and Current Regulator drivers; - SCSI subsystem; - SPI subsystem; - Media Oriented Systems Transport (MOST) driver; - Realtek RTL8723BS SDIO drivers; - TCM subsystem; - USB Host Controller drivers; - USB Type-C Connector System Software Interface driver; - Backlight driver; - Watchdog drivers; - BFS file system; - BTRFS file system; - Ext4 file system; - F2FS file system; - FUSE (File system in Userspace); - HFS+ file system; - File systems infrastructure; - Journaling layer for block devices (JBD2); - Network file system (NFS) client; - File system notification infrastructure; - NTFS3 file system; - OCFS2 file system; - SMB network file system; - BPF subsystem; - Ethernet bridge; - io_uring subsystem; - Locking primitives; - Scheduler infrastructure; - Shadow Call Stack mechanism; - Tracing infrastructure; - Memory management; - CAIF protocol; - Ceph Core library; - Networking core; - Ethtool driver; - Handshake API; - HSR network protocol; - IPv4 networking; - IPv6 networking; - MAC80211 subsystem; - Multipath TCP; - Netfilter; - NET/ROM layer; - NFC subsystem; - Open vSwitch; - Rose network layer; - Network traffic control; - Network sockets; - Sun RPC protocol; - Integrity Measurement Architecture(IMA) framework; - Key management; - Simplified Mandatory Access Control Kernel framework; - FireWire sound drivers; - HD-audio driver; - Turtle Beach Wavefront ALSA driver; - STMicroelectronics SoC drivers; - USB sound devices; - KVM subsystem; (CVE-2024-57795, CVE-2025-22022, CVE-2025-22111, CVE-2025-38022, CVE-2025-38234, CVE-2025-40164, CVE-2025-40325, CVE-2025-68206, CVE-2025-68254, CVE-2025-68255, CVE-2025-68256, CVE-2025-68257, CVE-2025-68258, CVE-2025-68259, CVE-2025-68261, CVE-2025-68263, CVE-2025-68264, CVE-2025-68265, CVE-2025-68266, CVE-2025-68291, CVE-2025-68325, CVE-2025-68332, CVE-2025-68335, CVE-2025-68336, CVE-2025-68337, CVE-2025-68344, CVE-2025-68345, CVE-2025-68346, CVE-2025-68347, CVE-2025-68349, CVE-2025-68354, CVE-2025-68362, CVE-2025-68363, CVE-2025-68364, CVE-2025-68366, CVE-2025-68367, CVE-2025-68369, CVE-2025-68371, CVE-2025-68372, CVE-2025-68374, CVE-2025-68378, CVE-2025-68379, CVE-2025-68380, CVE-2025-68724, CVE-2025-68727, CVE-2025-68728, CVE-2025-68732, CVE-2025-68733, CVE-2025-68740, CVE-2025-68741, CVE-2025-68742, CVE-2025-68744, CVE-2025-68753, CVE-2025-68755, CVE-2025-68756, CVE-2025-68757, CVE-2025-68758, CVE-2025-68759, CVE-2025-68763, CVE-2025-68764, CVE-2025-68765, CVE-2025-68766, CVE-2025-68767, CVE-2025-68769, CVE-2025-68770, CVE-2025-68771, CVE-2025-68772, CVE-2025-68773, CVE-2025-68774, CVE-2025-68775, CVE-2025-68776, CVE-2025-68777, CVE-2025-68778, CVE-2025-68780, CVE-2025-68782, CVE-2025-68783, CVE-2025-68785, CVE-2025-68786, CVE-2025-68787, CVE-2025-68788, CVE-2025-68794, CVE-2025-68795, CVE-2025-68796, CVE-2025-68797, CVE-2025-68798, CVE-2025-68799, CVE-2025-68800, CVE-2025-68801, CVE-2025-68804, CVE-2025-68806, CVE-2025-68808, CVE-2025-68809, CVE-2025-68810, CVE-2025-68811, CVE-2025-68813, CVE-2025-68814, CVE-2025-68815, CVE-2025-68816, CVE-2025-68817, CVE-2025-68818, CVE-2025-68819, CVE-2025-68820, CVE-2025-68821, CVE-2025-71064, CVE-2025-71065, CVE-2025-71066, CVE-2025-71067, CVE-2025-71068, CVE-2025-71069, CVE-2025-71071, CVE-2025-71072, CVE-2025-71075, CVE-2025-71077, CVE-2025-71078, CVE-2025-71079, CVE-2025-71081, CVE-2025-71082, CVE-2025-71083, CVE-2025-71084, CVE-2025-71085, CVE-2025-71086, CVE-2025-71087, CVE-2025-71088, CVE-2025-71089, CVE-2025-71091, CVE-2025-71093, CVE-2025-71094, CVE-2025-71095, CVE-2025-71096, CVE-2025-71097, CVE-2025-71098, CVE-2025-71101, CVE-2025-71102, CVE-2025-71104, CVE-2025-71105, CVE-2025-71107, CVE-2025-71108, CVE-2025-71109, CVE-2025-71111, CVE-2025-71112, CVE-2025-71113, CVE-2025-71114, CVE-2025-71116, CVE-2025-71118, CVE-2025-71119, CVE-2025-71120, CVE-2025-71121, CVE-2025-71122, CVE-2025-71123, CVE-2025-71125, CVE-2025-71126, CVE-2025-71127, CVE-2025-71130, CVE-2025-71131, CVE-2025-71132, CVE-2025-71133, CVE-2025-71135, CVE-2025-71136, CVE-2025-71137, CVE-2025-71138, CVE-2025-71140, CVE-2025-71141, CVE-2025-71143, CVE-2025-71144, CVE-2025-71147, CVE-2025-71148, CVE-2025-71149, CVE-2025-71150, CVE-2025-71151, CVE-2025-71153, CVE-2025-71154, CVE-2026-23209)

It was discovered that follow-redirects did not properly protect sensitive user information during redirects. An attacker could possibly use this issue to expose sensitive information. This issue only affected Ubuntu 18.04 LTS and Ubuntu 20.04 LTS. (CVE-2022-0155) It was discovered that follow-redirects did not properly remove sensitive information before storage or transfer. An attacker could possibly use this issue to expose sensitive information. This issue only affected Ubuntu 18.04 LTS and Ubuntu 20.04 LTS. (CVE-2022-0536) It was discovered that follow-redirects did not properly validate URLs when handling certain inputs. An attacker could possibly use this issue to redirect users to a malicious site, resulting in information disclosure or phishing attacks. (CVE-2023-26159) It was discovered that follow-redirects did not properly clear proxy authentication headers during cross-domain redirects. An attacker could possibly use this issue to cause exposure of sensitive credentials. (CVE-2024-28849)

USN-8190-1 fixed a vulnerability in Rack::Session. This update provides the corresponding update for Ubuntu 26.04 LTS. Original advisory details: SeungMyung Lee discovered that Rack::Session did not properly reject cookies upon decryption failure. A remote attacker could use this issue to manipulate session contents and possibly gain unauthorized access.

USN-8136-1 fixed vulnerabilities in Dovecot. The update caused a regression on Ubuntu 22.04 LTS and Ubuntu 24.04 LTS. This update fixes the problem. We apologize for the inconvenience. Original advisory details: It was discovered that Dovecot incorrectly handled invalid base64 SASL data. An attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 25.10. (CVE-2025-59028) It was discovered that Dovecot script decode2text.sh incorrectly handled zip files. An attacker could possibly use this issue to obtain sensitive information. (CVE-2025-59031) It was discovered that Dovecot incorrectly handled certain AUTHENTICATE requests. An attacker could possibly use this issue to cause a denial of service. (CVE-2025-59032) It was discovered that Dovecot incorrectly handled certain SQL based authentication. An attacker could possibly use this issue to bypass authentication. This issue only affected Ubuntu 25.10. (CVE-2026-24031) It was discovered that Dovecot incorrectly handled certain LDAP based authentication. An attacker could possibly use this issue to bypass restrictions and allow probing of LDAP structure. This issue only affected Ubuntu 25.10. (CVE-2026-27860) It was discovered that Dovecot is vulnerable to replay attack under certain conditions. An attacker could possibly use this issue to bypass authentication. (CVE-2026-27855) It was discovered that Dovecot is vulnerable to a timing attack under certain conditions. An attacker could possibly use this issue to bypass authentication. (CVE-2026-27856) It was discovered that Dovecot incorrectly handled certain IMAP login requests. An attacker could possibly use this issue to cause a denial of service. (CVE-2026-27857) It was discovered that Dovecot incorrectly handled certain specially crafted messages. An attacker could possibly use this issue to cause a denial of service. (CVE-2026-27858) It was discovered that Dovecot incorrectly handled certain specially crafted mail messages. An attacker could possibly use this issue to cause a denial of service. (CVE-2026-27859) It was discovered that Dovecot incorrectly handles file paths. A attacker could possibly use this issue to perform a path traversal and obtain or modify arbitrary files. This issue only affected Ubuntu 22.04 LTS and Ubuntu 24.04 LTS. (CVE-2026-0394)

USN-8087-1 fixed a vulnerability in python-cryptography. This update provides the corresponding update to Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. Original advisory details: It was discovered that python-cryptography incorrectly handled subgroup validation for SECT curves. A remote attacker could use this issue to perform a subgroup attack and possibly recover the least significant bits of private keys.

It was discovered that NLTK incorrectly handled file extraction when opening a maliciously crafted zip file. An attacker could possibly use this issue to create or overwrite files on the system and execute arbitrary code.

Ludvig Pedersen discovered that the System.Security.Cryptography.Xml library in .NET incorrectly handled certain XML inputs. An attacker could possibly use this issue to consume excessive resources, resulting in a denial of service. (CVE-2026-33116, CVE-2026-26171) Ludvig Pedersen and Kevin Jones discovered that the System.Security.Cryptography.Xml library in .NET incorrectly handled certain XML inputs. An attacker could possibly use this issue to cause .NET to crash, resulting in a denial of service. (CVE-2026-32203) Ludvig Pedersen discovered that the System.Net.Mail component in .NET incorrectly handled certain inputs. An attacker could possibly use this issue to perform a network spoofing attack. (CVE-2026-32178) It was discovered that the Microsoft.AspNetCore.DataProtection library in .NET did not properly verify cryptographic signatures under certain conditions. A remote attacker could possibly use this issue to elevate privileges. (CVE-2026-40372)

It was discovered that the Microsoft.AspNetCore.DataProtection library in .NET did not properly verify cryptographic signatures under certain conditions. A remote attacker could possibly use this issue to elevate privileges.

USN-8202-1 fixed vulnerabilities in jq. This update provides the corresponding update to Ubuntu 26.04 LTS. Original advisory details: It was discovered that jq did not correctly handle certain string concatenations. An attacker could possibly use this issue to cause a denial of service or execute arbitrary code. (CVE-2026-32316) It was discovered that jq did not correctly handle recursion in certain circumstances. An attacker could possibly use this issue to cause a denial of service. (CVE-2026-33947) It was discovered that jq did not correctly handle improperly terminated strings. An attacker could possibly use this issue to cause a denial of service or execute arbitrary code. (CVE-2026-33948) It was discovered that jq did not correctly handle checking certain variable types. An attacker could possibly use this issue to cause a denial of service or leak sensitive information. (CVE-2026-39956) It was discovered that jq did not correctly handle certain string formatting. An attacker could possibly use this issue to leak sensitive information or cause a denial of service. (CVE-2026-39979) It was discovered that jq used a fixed seed for hash table operations. An attacker could possibly use this issue to cause a denial of service. (CVE-2026-40164)

Michał Majchrowicz discovered that Vim's zip plugin could overwrite arbitrary files. An attacker could possibly use this issue to delete sensitive data or execute arbitrary code. This issue only affected Ubuntu 24.04 LTS and Ubuntu 25.10. (CVE-2026-35177) It was discovered that Vim's netbeans interface did not properly sanitize certain strings. An attacker could possibly use this issue to execute arbitrary commands. (CVE-2026-39881)

It was discovered that authd incorrectly assigned the primary group ID to users under certain conditions. A local attacker could possibly use this issue to achieve privilege escalation, or gain unauthorized access to files belonging to other users.

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-2026-23119, 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)