https://ubuntu.com/security/notices/rss.xmlRecent content on Ubuntu security notices2026 Canonical Ltd. Ubuntu and Canonical are registered trademarks of Canonical Ltd.http://www.rssboard.org/rss-specificationFeedgenWed, 30 Sep 2026 13:09:05 +0000https://ubuntu.com/security/notices/USN-8851-1Several 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 file system (NFS) server daemon; - IPv6 networking; - Netfilter; (CVE-2025-38724, CVE-2026-53131, CVE-2026-53221) https://ubuntu.com/security/notices/USN-8851-1Wed, 30 Sep 2026 09:53:51 +0000https://ubuntu.com/security/notices/USN-8850-1Several 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 file system (NFS) server daemon; - OCFS2 file system; - IPv6 networking; - Netfilter; - SCTP protocol; (CVE-2025-38724, CVE-2026-53043, CVE-2026-53131, CVE-2026-53221, CVE-2026-53224, CVE-2026-53225, CVE-2026-53246, CVE-2026-53309) https://ubuntu.com/security/notices/USN-8850-1Wed, 30 Sep 2026 08:10:36 +0000https://ubuntu.com/security/notices/USN-8849-1It was discovered that some Arm processors could complete a broadcast translation lookaside buffer (TLB) invalidation before memory writes made through the invalidated translation were globally observed. A local attacker could possibly use this to write to memory after permission to do so had been revoked, bypassing memory protections or escalating privileges. (CVE-2025-10263) 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; - InfiniBand drivers; - Network drivers; - TCM subsystem; - exFAT file system; - Network file system (NFS) server daemon; - B.A.T.M.A.N. meshing protocol; - IPv4 networking; - IPv6 networking; - Netfilter; - RDS protocol; (CVE-2026-53186, CVE-2026-53221, CVE-2026-53354, CVE-2026-53355, CVE-2026-53398, CVE-2026-63808, CVE-2026-63887, CVE-2026-63888, CVE-2026-63912, CVE-2026-63922, CVE-2026-63924, CVE-2026-63984, CVE-2026-63992, CVE-2026-63993, CVE-2026-63994, CVE-2026-64007, CVE-2026-64091) https://ubuntu.com/security/notices/USN-8849-1Wed, 30 Sep 2026 08:04:30 +0000https://ubuntu.com/security/notices/USN-8818-4It was discovered that some Arm processors could complete a broadcast translation lookaside buffer (TLB) invalidation before memory writes made through the invalidated translation were globally observed. A local attacker could possibly use this to write to memory after permission to do so had been revoked, bypassing memory protections or escalating privileges. (CVE-2025-10263) 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; - InfiniBand drivers; - Network drivers; - TCM subsystem; - exFAT file system; - Network file system (NFS) client; - Network file system (NFS) server daemon; - B.A.T.M.A.N. meshing protocol; - IPv4 networking; - IPv6 networking; - Netfilter; - RDS protocol; (CVE-2026-53186, CVE-2026-53216, CVE-2026-53221, CVE-2026-53354, CVE-2026-53355, CVE-2026-53398, CVE-2026-63800, CVE-2026-63808, CVE-2026-63887, CVE-2026-63888, CVE-2026-63912, CVE-2026-63922, CVE-2026-63924, CVE-2026-63984, CVE-2026-63992, CVE-2026-63993, CVE-2026-63994, CVE-2026-64007, CVE-2026-64091) https://ubuntu.com/security/notices/USN-8818-4Wed, 30 Sep 2026 08:00:27 +0000https://ubuntu.com/security/notices/USN-8817-2It was discovered that some Arm processors could complete a broadcast translation lookaside buffer (TLB) invalidation before memory writes made through the invalidated translation were globally observed. A local attacker could possibly use this to write to memory after permission to do so had been revoked, bypassing memory protections or escalating privileges. (CVE-2025-10263) 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; - InfiniBand drivers; - Network drivers; - TCM subsystem; - B.A.T.M.A.N. meshing protocol; - HSR network protocol; - IPv4 networking; - IPv6 networking; - Netfilter; - RDS protocol; (CVE-2026-53131, CVE-2026-53186, CVE-2026-53216, CVE-2026-53221, CVE-2026-53354, CVE-2026-53355, CVE-2026-63886, CVE-2026-63887, CVE-2026-63888, CVE-2026-63912, CVE-2026-63922, CVE-2026-63924, CVE-2026-63984, CVE-2026-63992, CVE-2026-63993, CVE-2026-63994, CVE-2026-64000, CVE-2026-64007, CVE-2026-64091) https://ubuntu.com/security/notices/USN-8817-2Wed, 30 Sep 2026 08:00:26 +0000https://ubuntu.com/security/notices/USN-8730-7A security issue was discovered in the Linux kernel. An attacker could possibly use this to compromise the system. This update corrects flaws in the following subsystems: - IPv6 networking; - Netfilter; https://ubuntu.com/security/notices/USN-8730-7Wed, 30 Sep 2026 08:00:26 +0000https://ubuntu.com/security/notices/USN-8819-4Several 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 file system (NFS) server daemon; - IPv6 networking; - Netfilter; (CVE-2025-38724, CVE-2026-53131, CVE-2026-53221) https://ubuntu.com/security/notices/USN-8819-4Wed, 30 Sep 2026 08:00:26 +0000https://ubuntu.com/security/notices/USN-8847-2USN-8847-1 fixed vulnerabilities in OpenSSL. This update provides the corresponding fix for OpenSSL on Ubuntu 14.04 LTS, Ubuntu 16.04 LTS, Ubuntu 18.04 LTS and Ubuntu 20.04 LTS. Original advisory details: It was discovered that OpenSSL incorrectly handled certain certificate revocation list distribution point names. An attacker could possibly use this issue to cause OpenSSL to consume excessive memory, resulting in a denial of service. (CVE-2026-35189) It was discovered that OpenSSL incorrectly implemented scalar multiplication for non-NIST elliptic curves. An attacker could possibly use this issue to perform a timing side-channel attack and obtain sensitive information. This issue only affected Ubuntu 18.04 LTS and Ubuntu 20.04 LTS. (CVE-2026-54872) It was discovered that OpenSSL incorrectly implemented SM2 signature generation. An attacker could possibly use this issue to perform a timing side-channel attack and obtain sensitive information. This issue only affected Ubuntu 18.04 LTS and Ubuntu 20.04 LTS. (CVE-2026-77696) It was discovered that OpenSSL incorrectly handled DTLS retransmission of handshake messages. An attacker could possibly use this issue to cause incorrect handshake behavior or a denial of service. (CVE-2026-84782)https://ubuntu.com/security/notices/USN-8847-2Tue, 29 Sep 2026 23:28:05 +0000https://ubuntu.com/security/notices/USN-8847-1It was discovered that OpenSSL incorrectly handled certain certificate revocation list distribution point names. An attacker could possibly use this issue to cause OpenSSL to consume excessive memory, resulting in a denial of service. (CVE-2026-35189) It was discovered that OpenSSL incorrectly handled QUIC unvalidated amplification credit accounting. An attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-35191) It was discovered that OpenSSL incorrectly implemented scalar multiplication for non-NIST elliptic curves. An attacker could possibly use this issue to perform a timing side-channel attack and obtain sensitive information. (CVE-2026-54872) It was discovered that OpenSSL incorrectly implemented SM2 scalar multiplication on ARM64 and RISC-V architectures. An attacker could possibly use this issue to perform a timing side-channel attack and obtain sensitive information. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-54875) It was discovered that OpenSSL incorrectly handled SSL context switching during a TLS handshake. An attacker could possibly use this issue to cause an out-of-bounds read, resulting in a denial of service or obtaining sensitive information. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-72897) It was discovered that OpenSSL incorrectly enforced QUIC connection- level flow control for streams. An attacker could possibly use this issue to cause OpenSSL to consume excessive memory, resulting in a denial of service. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-75804) It was discovered that OpenSSL incorrectly handled a NULL pointer in CMP client revocation response processing. An attacker could possibly use this issue to cause a denial of service. (CVE-2026-75805) It was discovered that OpenSSL incorrectly handled undersized DTLS 1.2 AEAD records before authentication. An attacker could possibly use this issue to cause a denial of service. (CVE-2026-75806) It was discovered that OpenSSL incorrectly implemented SM2 signature generation. An attacker could possibly use this issue to perform a timing side-channel attack and obtain sensitive information. (CVE-2026-77696) It was discovered that OpenSSL incorrectly handled DTLS retransmission of handshake messages. An attacker could possibly use this issue to cause incorrect handshake behavior or a denial of service. (CVE-2026-84782) It was discovered that OpenSSL incorrectly handled QUIC RETIRE_CONNECTION_ID frames. An attacker could possibly use this issue to cause OpenSSL to consume excessive memory, resulting in a denial of service. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-84784)https://ubuntu.com/security/notices/USN-8847-1Tue, 29 Sep 2026 18:19:43 +0000https://ubuntu.com/security/notices/USN-8846-1Yuqi Qiu and Xiang Li discovered that libheif incorrectly handled certain compressed metadata. A remote attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 24.04 LTS and Ubuntu 26.04 LTS. (CVE-2026-84384) Yuqi Qiu and Xiang Li discovered that libheif incorrectly handled certain HEIF sequence data. A remote attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-84446) Yuqi Qiu and Xiang Li discovered that libheif incorrectly handled certain image references. A remote attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-84447) It was discovered that libheif incorrectly handled certain region masks. A local attacker could possibly use this issue to obtain sensitive information or cause a denial of service. This issue only affected Ubuntu 24.04 LTS and Ubuntu 26.04 LTS. (CVE-2026-84448) It was discovered that libheif incorrectly handled certain images. A remote attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, and Ubuntu 24.04 LTS. (CVE-2026-84449)https://ubuntu.com/security/notices/USN-8846-1Tue, 29 Sep 2026 16:18:50 +0000