Ubuntu Security Advisories

It was discovered that OpenImageIO incorrectly performed bounds checking when processing SGI files. An attacker could possibly use this issue to cause a denial of service or execute arbitrary code. (CVE-2026-43903) It was discovered that OpenImageIO incorrectly handled run-length encoding when processing Softimage PIC files. An attacker could possibly use this issue to cause a denial of service or execute arbitrary code. (CVE-2026-43904) It was discovered that OpenImageIO incorrectly validated subimage metadata when processing HEIF files. An attacker could possibly use this issue to cause a denial of service or execute arbitrary code. This issue only affected Ubuntu 20.04 LTS, Ubuntu 24.04 LTS and Ubuntu 26.04 LTS. (CVE-2026-43906) It was discovered that OpenImageIO contained multiple integer overflow vulnerabilities when processing DPX files. An attacker could possibly use these issues to cause a denial of service or execute arbitrary code. (CVE-2026-43907, CVE-2026-43908, CVE-2026-43909)

It was discovered that rabbitmq-c exposed credentials in command-line arguments under certain circumstances. A local attacker could possibly use this issue to obtain sensitive information. This issue only affected Ubuntu 22.04 LTS and Ubuntu 24.04 LTS. (CVE-2023-35789) It was discovered that rabbitmq-c incorrectly handled AMQP frame lengths under certain circumstances, which could lead to an out-of-bounds read. A remote attacker could possibly use this issue to cause rabbitmq-c to crash, resulting in a denial of service. (CVE-2026-44235) It was discovered that rabbitmq-c incorrectly handled AMQP login handshakes under certain circumstances, which could lead to a heap buffer overflow. A remote attacker could possibly use this issue to cause rabbitmq-c to crash, resulting in a denial of service, or execute arbitrary code. (CVE-2026-44236)

It was discovered that OpenStack Keystone allowed restricted application credentials to create EC2 credentials. An authenticated attacker with only a reader role could possibly use this issue to bypass the role restrictions imposed on the application credential. (CVE-2026-33551) It was discovered that the OpenStack Keystone LDAP identity backend did not correctly convert the user enabled attribute to a boolean value. An attacker could possibly use this issue to authenticate as a user disabled in LDAP. This issue only affected Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, and Ubuntu 25.10. (CVE-2026-40683) It was discovered that OpenStack Keystone's application credential authentication plugin did not verify that the user supplied in an authentication request matched the credential owner. An authenticated attacker could possibly impersonate another user and gain access to their tokens and credentials. (CVE-2026-42998) It was discovered that OpenStack Keystone's RBAC policy enforcer unconditionally merged the raw JSON request body into the policy enforcement dictionary, overwriting trusted target data. An authenticated attacker could possibly use this issue to inject arbitrary policy attributes to bypass RBAC checks. (CVE-2026-42999) It was discovered that OpenStack Keystone allowed an attacker with the member role to escalate privileges to admin by chaining application credential impersonation with Keystone trusts. An attacker could possibly use this issue to create a persistent trust delegating the victim's admin role to themselves. (CVE-2026-43000) It was discovered that OpenStack Keystone did not validate that the project_id for an EC2 credential matched the project of the authenticating application credential. An attacker with valid credentials for one project could possibly use this issue to create EC2 credentials targeting a different project. (CVE-2026-43001) It was discovered that OpenStack Keystone's federated token rescoping mechanism did not propagate the original token's expiry to the newly issued token. A remote attacker could possibly use this issue to maintain access indefinitely by repeatedly rescoping tokens before expiry. (CVE-2026-44394)

It was discovered that FreeRDP incorrectly handled memory under certain circumstances, which could lead to an out-of-bounds heap write. An attacker could possibly use this issue to cause a denial of service or execute arbitrary code. (CVE-2026-45700) In addition, this update fixes a regression introduced in USN-8105-1. The update introduces a complete fix for CVE-2026-22858, CVE-2026-23732 and CVE-2026-25952 in Ubuntu 24.04 LTS and Ubuntu 25.10.

USN-8349-1 fixed vulnerabilities in rsync. Unfortunately that update introduced multiple regressions in rsync functionality. This update fixes the problem. We apologize for the inconvenience. Original advisory details: 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. (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)

It was discovered that Ruby's Net::IMAP library did not properly verify that Transport Layer Security (TLS) encryption was started after issuing a STARTTLS command. A remote attacker could possibly use this issue to perform a machine-in-the-middle attack and silently bypass TLS encryption. (CVE-2026-42246) It was also discovered that Ruby's Net::IMAP library did not validate string arguments passed to certain commands. A remote attacker could possibly use this issue to inject arbitrary IMAP commands. (CVE-2026-42257)

It was discovered that ADSys did not properly handle certain HTTP/2 frames. A remote attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-27141) It was discovered that ADSys did not properly handle certain HTTP/2 SETTINGS frames. A remote attacker could possibly use this issue to cause a denial of service. (CVE-2026-33814)

It was discovered that tmux incorrectly handled image cleanup, leading to a use-after-free vulnerability. A local attacker could possibly use this issue to cause tmux to crash, resulting in a denial of service.

USN-8398-1 fixed a vulnerability in nginx. The update caused a regression and was temporarily reverted in USN-8398-2. This update introduces a complete fix for CVE-2026-49975. We apologize for the inconvenience. Original advisory details: It was discovered that nginx incorrectly handled certain cookie headers in the HTTP/2 implementation. A remote attacker could possibly use this issue to cause nginx to consume excessive resources, resulting in a denial of service.

USN-8405-1 fixed vulnerabilities in CUPS. The update introduced a regression that cause CUPS to crash when parsing certain large printer PPD files. This update fixes the problem. Original advisory details: Ariel Silver discovered that CUPS incorrectly handled username comparisons during authorization checks. A local attacker could possibly use this issue to gain unauthorized access to restricted operations. (CVE-2026-27447) Asim Viladi Oglu Manizada discovered that CUPS incorrectly handled notify-recipient-uri values in the RSS notifier. A remote attacker could possibly use this issue to overwrite lp-writable files and cause a denial of service. (CVE-2026-34978) Jacob Newman discovered that CUPS incorrectly handled filter option strings when processing job attributes. An attacker could use this issue to cause CUPS to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2026-34979) Asim Viladi Oglu Manizada discovered that CUPS incorrectly handled page-border values in shared PostScript queues. A remote attacker could possibly use this issue to execute arbitrary code. (CVE-2026-34980) Asim Viladi Oglu Manizada discovered that CUPS incorrectly handled localhost authentication to attacker-controlled IPP services. A local attacker could possibly use this issue to overwrite arbitrary files and execute arbitrary code. (CVE-2026-34990) Tomer Fichman discovered that CUPS incorrectly handled negative job-password-supported values. A local attacker could possibly use this issue to cause CUPS to crash, resulting in a denial of service. (CVE-2026-39314) Tomer Fichman discovered that CUPS incorrectly handled temporary printer deletion. An attacker could possibly use this issue to cause CUPS to crash, resulting in a denial of service, or to execute arbitrary code. (CVE-2026-39316) Tomer Fichman discovered that CUPS incorrectly handled certain malformed SNMP responses. An attacker could possibly use this issue to obtain sensitive information. (CVE-2026-41079)

It was discovered that Mesa did not properly validate memory allocation sizes in WebGPU under certain circumstances. An attacker could use this issue to cause Mesa to crash, resulting in a denial of service, or possibly execute arbitrary code.

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) It was discovered that the Linux kernel did not properly handle shared page fragments during socket buffer operations, collectively known as Dirty Frag. A logic flaw existed in the XFRM ESP-in-TCP subsystem and in the RxRPC networking subsystem when processing paged fragments. A local attacker could use this to escalate privileges, or possibly escape a container. (CVE-2026-43284, CVE-2026-43500) It was discovered that a logic flaw existed in the XFRM ESP-in-TCP subsystem in the Linux kernel when handling socket buffer fragments. This flaw is known as Fragnesia. A local attacker could use this to escalate privileges, or possibly escape a container. (CVE-2026-43503, CVE-2026-46300) Qualys discovered that a race condition existed in the ptrace subsystem of the Linux kernel when privileged processes are exiting. An unprivileged local attacker could use this issue to expose sensitive information. (CVE-2026-46333) 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; - RDS protocol; - 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, CVE-2026-43494, CVE-2026-46028)

It was discovered that lwIP contained a buffer overflow in the EAP authentication handling code. An attacker could possibly use this issue to trigger a buffer overflow, resulting in arbitrary code execution or a denial of service. This issue only affected Ubuntu 20.04 LTS. (CVE-2020-8597) It was discovered that lwIP incorrectly handled certain ICMPv6 or 6LoWPAN packets. An attacker could possibly use this issue to trigger a buffer overflow, resulting in information disclosure. This issue only affected Ubuntu 20.04 LTS. (CVE-2020-22283, CVE-2020-22284) It was discovered that lwIP did not properly validate certain SNMPv3 authentication parameters. An attacker could possibly use this issue to trigger a stack-based buffer overflow, resulting in arbitrary code execution or a denial of service. (CVE-2026-8836)

It was discovered that Ubuntu Kylin Software Center incorrectly handled user-supplied input in its D-Bus service. A local attacker could possibly use this issue to gain administrative privileges.

Eduardo Gonzalez Gutierrez and Arnaud Morin discovered that Mistral did not properly enforce access policies on some API endpoints. An attacker could possibly execute arbitrary code on a Mistral worker and possibly extract sensitive data including service credentials from it.

Dmitry Tantsur and Tuomo Tanskanen discovered that Ironic did not properly validate file paths when handling ISO images. A privileged authenticated remote user could use this issue to perform path traversal via a crafted ISO image and overwrite arbitrary files on the Ironic conductor. (CVE-2026-48681) Dmitry Tantsur and Tuomo Tanskanen discovered that Ironic did not properly validate kernel command line parameters. A privileged authenticated remote user could use this issue to inject scripts during node boot and possibly execute arbitrary code. (CVE-2026-46447) Dmitry Tantsur and Tuomo Tanskanen discovered that Ironic incorrectly restricted access to custom PXE templates. A privileged authenticated remote user could use this issue to read arbitrary sensitive files on the Ironic conductor. (CVE-2026-44917)

It was discovered that .NET did not properly handle link resolution before file access. A local attacker could use this issue to perform unauthorized file tampering and write arbitrary files outside of the intended extraction directory. (CVE-2026-45491) It was discovered that .NET did not properly handle deeply-nested MessagePack arrays. An attacker could use this to cause .NET to consume excessive resources, resulting in a denial of service. (CVE-2026-45591)

It was discovered that HTTP-Daemon incorrectly handled untrusted input under certain circumstances. A remote attacker could possibly use this issue to execute arbitrary commands, create or overwrite arbitrary files, or expose sensitive information.

USN-6455-1 fixed vulnerabilities in Exim. The fix for CVE-2023-42117 introduced a regression on Ubuntu 22.04 LTS that resulted in certain connections logging a Taint mismatch error. This update fixes the problem. We apologize for the inconvenience. Original advisory details: It was discovered that Exim incorrectly handled validation of user-supplied data, which could lead to memory corruption. A remote attacker could possibly use this issue to execute arbitrary code. (CVE-2023-42117) It was discovered that Exim incorrectly handled validation of user-supplied data, which could lead to an out-of-bounds read. An attacker could possibly use this issue to expose sensitive information. (CVE-2023-42119)

USN-8130-1 fixed a vulnerability in GStreamer Base Plugins. This update provides the corresponding update for Ubuntu 16.04 LTS. Original advisory details: It was discovered that GStreamer Base Plugins incorrectly handled certain AVI media files. A remote attacker could use this issue to cause GStreamer Base Plugins to crash, resulting in a denial of service, or possibly execute arbitrary code.