How severe is CVE-2016-20021?

CVE-2016-20021 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-2016-20021 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-20021?

CVE-2016-20021 affects Gentoo Portage. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2016-20021?

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.

Does CVE-2016-20021 have an EU (EUVD) identifier?

Yes. CVE-2016-20021 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-0149.

When was CVE-2016-20021 published?

CVE-2016-20021 was published on 2024-01-12 and last updated on 2026-06-17.

CVE-2016-20021

CVE-2016-20021 is a critical-severity vulnerability in Gentoo Portage 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-347.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 0% (37th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-0149
Weakness: CWE-347
Affected product: Gentoo Portage
Published: 2024-01-12
Last modified: 2026-06-17

Description

In Gentoo Portage before 3.0.47, there is missing PGP validation of executed code: the standalone emerge-webrsync downloads a .gpgsig file but does not perform signature verification. Unless emerge-webrsync is used, Portage is not vulnerable.

Frequently asked questions

What is CVE-2016-20021?: In Gentoo Portage before 3.0.47, there is missing PGP validation of executed code: the standalone emerge-webrsync downloads a .gpgsig file but does not perform signature verification. Unless emerge-webrsync is used, Portage is not vulnerable.
How severe is CVE-2016-20021?: CVE-2016-20021 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-2016-20021 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-20021?: CVE-2016-20021 affects Gentoo Portage. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2016-20021?: 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.
Does CVE-2016-20021 have an EU (EUVD) identifier?: Yes. CVE-2016-20021 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-0149.
When was CVE-2016-20021 published?: CVE-2016-20021 was published on 2024-01-12 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:gentoo:portage:*:*:*:*:*:*:*:*

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