How severe is CVE-2016-20011?

CVE-2016-20011 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-2016-20011 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-20011?

CVE-2016-20011 affects Gnome Libgrss. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2016-20011?

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-2016-20011 published?

CVE-2016-20011 was published on 2021-05-25 and last updated on 2026-06-17.

CVE-2016-20011

CVE-2016-20011 is a high-severity vulnerability in Gnome Libgrss 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-295.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (71st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Gnome Libgrss
Published: 2021-05-25
Last modified: 2026-06-17

Description

libgrss through 0.7.0 fails to perform TLS certificate verification when downloading feeds, allowing remote attackers to manipulate the contents of feeds without detection. This occurs because of the default behavior of SoupSessionSync.

Frequently asked questions

What is CVE-2016-20011?: libgrss through 0.7.0 fails to perform TLS certificate verification when downloading feeds, allowing remote attackers to manipulate the contents of feeds without detection. This occurs because of the default behavior of SoupSessionSync.
How severe is CVE-2016-20011?: CVE-2016-20011 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-2016-20011 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-20011?: CVE-2016-20011 affects Gnome Libgrss. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2016-20011?: 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-2016-20011 published?: CVE-2016-20011 was published on 2021-05-25 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:gnome:libgrss:*:*:*:*:*:*:*:*

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