CVE-2026-5260
Publication date 30 April 2026
Last updated 6 July 2026
Ubuntu priority
Description
A flaw was found in libgnutls. A remote attacker, by sending an extremely short premaster secret during an RSA key exchange to a server using an RSA key backed by a PKCS#11 token, could trigger a short heap overread. This memory corruption vulnerability could lead to information disclosure.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| gnutls28 | 26.04 LTS resolute |
Fixed 3.8.12-2ubuntu1.1
|
| 25.10 questing |
Fixed 3.8.9-3ubuntu2.2
|
|
| 24.04 LTS noble |
Fixed 3.8.3-1.1ubuntu3.6
|
|
| 22.04 LTS jammy |
Fixed 3.7.3-4ubuntu1.9
|
|
| 20.04 LTS focal |
Fixed 3.6.13-2ubuntu1.12+esm2
|
|
| 18.04 LTS bionic |
Fixed 3.5.18-1ubuntu1.6+esm3
|
|
| 16.04 LTS xenial |
Not affected
|
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mrmajumder
xenial is not-affected: gnutls 3.4.10 uses the allocating decrypt API gnutls_privkey_decrypt_data() in both lib/auth/rsa.c and lib/auth/rsa_psk.c, where the callee (PKCS#11) allocates the plaintext to its real size, so the short heap overread cannot occur.
Severity score breakdown
CVSS version: CVSS v3.0
Base score
8.2 · High
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H
References
Related Ubuntu Security Notices (USN)
- USN-8284-1
- GnuTLS vulnerabilities
- 20 May 2026
- USN-8502-1
- GnuTLS vulnerabilities
- 6 July 2026