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Fencer Intel
medium 5.9

CVE-2015-8313 json

GnuTLS incorrectly validates the first byte of padding in CBC modes

published 6y ago modified 4mo ago also EUVD-2015-8199

cvss
5.9
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
1.7%
EPSS 1.7% chance of exploitation in 30 days, percentile 77%
public exploits
0
none known

Summary

GnuTLS incorrectly validates the first byte of padding in CBC modes

Patch / fix

  • gnutls26 Ubuntu 14.04 LTS 2.12.23-12ubuntu2.3

ubuntu advisories UBUNTU-CVE-2015-8313

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • gnutls SLES for SAP 11 SP4, SLES for SAP 11 SP3, SLES 11 SP4 +8 more 2.4.1-24.39.60.1

suse advisories SUSE-SU-2016:0077-1

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2015-8313 updated cvss 2.6

gnutls: First byte of the padding in CBC mode is not checked

  • Red Hat Enterprise Linux 5 gnutls Red Hat Enterprise Linux 6 gnutls, gnutls-guile, gnutls-utils Red Hat Enterprise Linux 7 gnutls, gnutls-c++, gnutls-dane, gnutls-utils
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

1.69% chance of exploitation in the next 30 days, higher than 77% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
NVD 3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
NVD 2.0 4.3 AV:N/AC:M/Au:N/C:P/I:N/A:N

Classification

Weakness

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.