Packages
- pyopenssl - Python wrapper around the OpenSSL library
Details
It was discovered that pyOpenSSL incorrectly handled exceptions in the
tlsext_servername callback. This could result in connections being
accepted after an exception, contrary to expectations. (CVE-2026-27448)
It was discovered that pyOpenSSL incorrectly handled the DTLS cookie
generation callback. If a callback provided cookie values greater than 256
bytes, an attacker could use this issue to cause pyOpenSSL to crash,
resulting in a denial of service, or possibly execute arbitrary code. This
issue only affected Ubuntu 24.04 LTS and Ubuntu 25.10. (CVE-2026-27459)
It was discovered that pyOpenSSL incorrectly handled exceptions in the
tlsext_servername callback. This could result in connections being
accepted after an exception, contrary to expectations. (CVE-2026-27448)
It was discovered that pyOpenSSL incorrectly handled the DTLS cookie
generation callback. If a callback provided cookie values greater than 256
bytes, an attacker could use this issue to cause pyOpenSSL to crash,
resulting in a denial of service, or possibly execute arbitrary code. This
issue only affected Ubuntu 24.04 LTS and Ubuntu 25.10. (CVE-2026-27459)
Update instructions
In general, a standard system update will 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 | ||
|---|---|---|---|
| 25.10 questing | python3-openssl – 25.0.0-1ubuntu0.1 | ||
| 24.04 LTS noble | python3-openssl – 23.2.0-1ubuntu0.1 | ||
| 22.04 LTS jammy | python3-openssl – 21.0.0-1ubuntu0.1 | ||
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