How severe is CVE-2020-12658?

CVE-2020-12658 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-2020-12658 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-2020-12658?

CVE-2020-12658 primarily affects Gssproxy Project Gssproxy. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-12658?

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-2020-12658 published?

CVE-2020-12658 was published on 2020-12-31 and last updated on 2026-06-17.

CVE-2020-12658

CVE-2020-12658 is a critical-severity vulnerability in Gssproxy Project Gssproxy 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-667.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 2% (74th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-667
Affected product: Gssproxy Project Gssproxy
Published: 2020-12-31
Last modified: 2026-06-17

Description

gssproxy (aka gss-proxy) before 0.8.3 does not unlock cond_mutex before pthread exit in gp_worker_main() in gp_workers.c. NOTE: An upstream comment states "We are already on a shutdown path when running the code in question, so a DoS there doesn't make any sense, and there has been no additional information provided us (as upstream) to indicate why this would be a problem.

Frequently asked questions

What is CVE-2020-12658?: gssproxy (aka gss-proxy) before 0.8.3 does not unlock cond_mutex before pthread exit in gp_worker_main() in gp_workers.c. NOTE: An upstream comment states "We are already on a shutdown path when running the code in question, so a DoS there doesn't make any sense, and there has been no additional information provided us (as upstream) to indicate why this would be a problem.
How severe is CVE-2020-12658?: CVE-2020-12658 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-2020-12658 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-2020-12658?: CVE-2020-12658 primarily affects Gssproxy Project Gssproxy. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-12658?: 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-2020-12658 published?: CVE-2020-12658 was published on 2020-12-31 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:gssproxy_project:gssproxy:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

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