ESB-2026.3480 — Vulnetix

ESB-2026.3480 PUBLISHED CVSS 9.300000190734863 CRITICAL

=========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2026.3480 USN-8155-2: OpenSSL vulnerabilities 10 April 2026 =========================================================================== AUSCERT Security Bulletin Summary --------------------------------- Product: OpenSSL Publisher: Ubuntu Operating System: Ubuntu Resolution: Patch/Upgrade CVE Names: CVE-2026-2673 CVE-2026-28387 CVE-2026-28388 CVE-2026-28389 CVE-2026-28390 CVE-2026-31789 CVE-2026-31790 Original Bulletin: https://ubuntu.com/security/notices/USN-8155-2 Comment: CVSS (Max): 7.5* CVE-2026-31790 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N) CVSS Source: [Ubuntu], Red Hat, SUSE Calculator: https://www.first.org/cvss/calculator/3.1#CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N * Not all CVSS available when published EPSS (Max): 0.0% (13th) CVE-2026-2673 2026-04-09 - --------------------------BEGIN INCLUDED TEXT-------------------- USN-8155-2: OpenSSL vulnerabilities Publication date 9 April 2026 Overview Several security issues were fixed in OpenSSL. Releases 20.04 LTS 18.04 LTS 16.04 LTS 14.04 LTS --------------------------------------------------------------------------------- Open side navigation Packages o openssl - Secure Socket Layer (SSL) cryptographic library and tools o openssl1.0 - Secure Socket Layer (SSL) cryptographic library and tools Details USN-8155-1 fixed vulnerabilities in OpenSSL. This update provides the corresponding updates for openssl and openssl1.0 packages for Ubuntu 14.04 LTS, Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. Original advisory details: Viktor Dukhovni discovered that OpenSSL incorrectly negotiated the expected preferred key exchange group when used as a TLS 1.3 server. This could result in a less preferred key exchange being used, contrary to expectations. This issue only affected Ubuntu 25.10. ( CVE-2026-2673 ) Igor Morgenstern discovered that OpenSSL incorrectly handled certain memory operations when used as a DANE client. A remote attacker could use this issue to cause OpenSSL to crash, resulting in a denial of service, or possibly execute arbitrary code. ( CVE-2026-28387 ) Igor Morgenstern discovered that OpenSSL incorrectly handled certain memory operations when processing a delta CRL. A remote attacker could possibly use this issue to cause OpenSSL to crash, resulting in a denial of service. ( CVE-2026-28388 ) Nathan Sportsman, Daniel Rhea, and Jaeho Nam discovered that OpenSSL incorrectly handled certain memory operations when processing a crafted CMS EnvelopedData message with KeyAgreeRecipientInfo. A remote attacker could possibly use this issue to cause OpenSSL to crash, resulting in a denial of service. ( CVE-2026-28389 ) Muhammad Daffa, Joshua Rogers, and Chanho Kim discovered that OpenSSL incorrectly handled processing of a crafted CMS EnvelopedData message with KeyTransportRecipientInfo. A remote attacker could possibly use this issue to cause OpenSSL to crash, resulting in a denial of service. ( CVE-2026-28390 ) Quoc Tran discovered that OpenSSL incorrectly handled hexadecimal conversion on 32-bit platforms. A remote attacker could use this issue to cause OpenSSL to crash, resulting in a denial of service, or possibly execute arbitrary code. ( CVE-2026-31789 ) Simo Sorce discovered that OpenSSL incorrectly handled failures in RSA KEM RSASVE Encapsulation. A remote attacker could possibly use this issue to obtain sensitive information. ( CVE-2026-31790 ) --------------------------------------------------------------------------------- Update instructions The problem can be corrected by updating your system to the following package versions: Ubuntu Package Version Release libssl1.1 - 1.1.1f-1ubuntu2.24+esm3 Ubuntu Pro Fix available with 20.04 LTS Ubuntu Pro . focal openssl - 1.1.1f-1ubuntu2.24+esm3 Ubuntu Pro Fix available with Ubuntu Pro . libssl1.0.0 - 1.0.2n-1ubuntu5.13+esm4 Ubuntu Pro Fix available with Ubuntu Pro . libssl1.1 - 1.1.1-1ubuntu2.1~18.04.23+esm8 Ubuntu Pro Fix available 18.04 LTS with Ubuntu Pro . bionic openssl - 1.1.1-1ubuntu2.1~18.04.23+esm8 Ubuntu Pro Fix available with Ubuntu Pro . openssl1.0 - 1.0.2n-1ubuntu5.13+esm4 Ubuntu Pro Fix available with Ubuntu Pro . libssl1.0.0 - 1.0.2g-1ubuntu4.20+esm15 Ubuntu Pro Fix available with 16.04 LTS Ubuntu Pro . xenial openssl - 1.0.2g-1ubuntu4.20+esm15 Ubuntu Pro Fix available with Ubuntu Pro . libssl1.0.0 - 1.0.1f-1ubuntu2.27+esm13 Ubuntu Pro Fix available with 14.04 LTS Ubuntu Pro via Legacy Support add-on. trusty openssl - 1.0.1f-1ubuntu2.27+esm13 Ubuntu Pro Fix available with Ubuntu Pro via Legacy Support add-on. --------------------------------------------------------------------------------- References o CVE-2026-28390 o CVE-2026-28389 o CVE-2026-28388 o CVE-2026-28387 Related notices o USN-8155-1 - --------------------------END INCLUDED TEXT---------------------- You have received this e-mail bulletin as a result of your organisation's registration with AUSCERT. 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It may not be updated when updates to the original are made. If downloading at a later date, it is recommended that the bulletin is retrieved directly from the author's website to ensure that the information is still current. Contact information for the authors of the original document is included in the Security Bulletin above. If you have any questions or need further information, please contact them directly. Previous advisories and external security bulletins can be retrieved from: https://portal.auscert.org.au/bulletins/ =========================================================================== AUSCERT The University of Queensland, Brisbane QLD 4072 Australia e: auscert@auscert.org.au t: +61 (0)7 3365 4417 Allies in Cyber Security ===========================================================================

Risk Scores

CVSS v4.0

9.300000190734863

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Affected Products

Vendor	Product	Versions
Ubuntu	OpenSSL

Timeline

Apr 9, 2026 CVE Published
Apr 10, 2026 Distribution Patch

References

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