CVE-2026-63825: gcov: use atomic counter updates to fix concurrent access crashes

mediumCVSS 5.5CVE-2026-63825

CSIRTS triage

vendor: Linux product: gcovOther

What: Concurrent access crashes can occur due to improper atomic counter updates in gcov.
Who is affected: Deployments using gcov for code coverage analysis.
Urgency: Remediation is necessary as the severity is unknown and exploitation is not confirmed.
Action: Apply the patch for CVE-2026-63825.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: medium — CVSS 5.5
Published: 2026-07-14
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-63825

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-638250.41% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 34% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-63825	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

criticalCVE-2026-63825: In the Linux kernel, the following vulnerability has been resolved: gcov: use atomic counter u…nvd

Recent advisories for gcov

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

criticalCVE-2026-63825: In the Linux kernel, the following vulnerability has been resolved: gcov: use atomic counter u…nvd · 2026-07-19