Packages
- openssl - Secure Socket Layer (SSL) cryptographic library and tools
- 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 CVE-2026-28387 for openssl in Ubuntu 20.04 LTS.
CVE-2026-28388 for openssl and openssl1.0 in Ubuntu 14.04 LTS, Ubuntu 16.04
LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS, and CVE-2026-28389 and
CVE-2026-28390 for openssl and openssl1.0 for 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...
USN-8155-1 fixed vulnerabilities in OpenSSL. This update provides the
corresponding updates for CVE-2026-28387 for openssl in Ubuntu 20.04 LTS.
CVE-2026-28388 for openssl and openssl1.0 in Ubuntu 14.04 LTS, Ubuntu 16.04
LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS, and CVE-2026-28389 and
CVE-2026-28390 for openssl and openssl1.0 for 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
After a standard system update you need to reboot your computer to make all the necessary changes.
Learn more about how to get the fixes.The problem can be corrected by updating your system to the following package versions:
| Ubuntu Release | Package Version | ||
|---|---|---|---|
| 20.04 LTS focal | libssl1.1 – 1.1.1f-1ubuntu2.24+esm3 | ||
| openssl – 1.1.1f-1ubuntu2.24+esm3 | |||
| 18.04 LTS bionic | libssl1.0.0 – 1.0.2n-1ubuntu5.13+esm4 | ||
| libssl1.1 – 1.1.1-1ubuntu2.1~18.04.23+esm8 | |||
| openssl – 1.1.1-1ubuntu2.1~18.04.23+esm8 | |||
| openssl1.0 – 1.0.2n-1ubuntu5.13+esm4 | |||
| 16.04 LTS xenial | libssl1.0.0 – 1.0.2g-1ubuntu4.20+esm15 | ||
| openssl – 1.0.2g-1ubuntu4.20+esm15 | |||
| 14.04 LTS trusty | libssl1.0.0 – 1.0.1f-1ubuntu2.27+esm13 | ||
| openssl – 1.0.1f-1ubuntu2.27+esm13 | |||
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