USN-8847-1 release notes and known issues

Summary

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 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)

Improvements and security content

• 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 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)

Affected products and versions

Recommended action

Review the official publisher document before deployment.

Lifecycle connections

These links connect the publisher update to related Lifecycle records without treating the update publication date as an end-of-support date.

Official publisher evidence