How severe is CVE-2016-7949?

CVE-2016-7949 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2016-7949 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-7949?

CVE-2016-7949 primarily affects X.org Libxrender. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-7949?

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

When was CVE-2016-7949 published?

CVE-2016-7949 was published on 2016-12-13 and last updated on 2026-06-17.

CVE-2016-7949

CVE-2016-7949 is a critical-severity vulnerability in X.org Libxrender with a CVSS 3.x base score of 9.8. 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: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 4% (88th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: X.org Libxrender
Published: 2016-12-13
Last modified: 2026-06-17

Description

Multiple buffer overflows in the (1) XvQueryAdaptors and (2) XvQueryEncodings functions in X.org libXrender before 0.9.10 allow remote X servers to trigger out-of-bounds write operations via vectors involving length fields.

Frequently asked questions

What is CVE-2016-7949?: Multiple buffer overflows in the (1) XvQueryAdaptors and (2) XvQueryEncodings functions in X.org libXrender before 0.9.10 allow remote X servers to trigger out-of-bounds write operations via vectors involving length fields.
How severe is CVE-2016-7949?: CVE-2016-7949 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2016-7949 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-7949?: CVE-2016-7949 primarily affects X.org Libxrender. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-7949?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2016-7949 published?: CVE-2016-7949 was published on 2016-12-13 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:x.org:libxrender:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:24:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:25:*:*:*:*:*:*:*

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