How severe is CVE-2016-4456?

CVE-2016-4456 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2016-4456 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-4456?

CVE-2016-4456 affects Gnu Gnutls. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2016-4456?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2016-4456 published?

CVE-2016-4456 was published on 2017-08-08 and last updated on 2026-06-17.

CVE-2016-4456

CVE-2016-4456 is a high-severity vulnerability in Gnu Gnutls with a CVSS 3.x base score of 7.5. 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-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (80th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Gnu Gnutls
Published: 2017-08-08
Last modified: 2026-06-17

Description

The "GNUTLS_KEYLOGFILE" environment variable in gnutls 3.4.12 allows remote attackers to overwrite and corrupt arbitrary files in the filesystem.

Frequently asked questions

What is CVE-2016-4456?: The "GNUTLS_KEYLOGFILE" environment variable in gnutls 3.4.12 allows remote attackers to overwrite and corrupt arbitrary files in the filesystem.
How severe is CVE-2016-4456?: CVE-2016-4456 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2016-4456 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-4456?: CVE-2016-4456 affects Gnu Gnutls. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2016-4456?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2016-4456 published?: CVE-2016-4456 was published on 2017-08-08 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:gnu:gnutls:3.4.12:*:*:*:*:*:*:*

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