How severe is CVE-2015-8313?

CVE-2015-8313 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2015-8313 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2015-8313?

CVE-2015-8313 primarily affects Gnu Gnutls. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2015-8313?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2015-8313 published?

CVE-2015-8313 was published on 2019-12-20 and last updated on 2026-06-17.

CVE-2015-8313

CVE-2015-8313 is a medium-severity vulnerability in Gnu Gnutls with a CVSS 3.x base score of 5.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-203.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 4.3
EPSS exploit prediction: 2% (74th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-203
Affected product: Gnu Gnutls
Published: 2019-12-20
Last modified: 2026-06-17

Description

GnuTLS incorrectly validates the first byte of padding in CBC modes

Frequently asked questions

What is CVE-2015-8313?: GnuTLS incorrectly validates the first byte of padding in CBC modes
How severe is CVE-2015-8313?: CVE-2015-8313 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2015-8313 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2015-8313?: CVE-2015-8313 primarily affects Gnu Gnutls. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2015-8313?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2015-8313 published?: CVE-2015-8313 was published on 2019-12-20 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:gnu:gnutls:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:7.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*

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