CVE-2021-29626

CVE-2021-29626 is a medium-severity vulnerability in Freebsd with a CVSS 3.x base score of 5.5. 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-416.

Key facts

Description

In FreeBSD 13.0-STABLE before n245117, 12.2-STABLE before r369551, 11.4-STABLE before r369559, 13.0-RC5 before p1, 12.2-RELEASE before p6, and 11.4-RELEASE before p9, copy-on-write logic failed to invalidate shared memory page mappings between multiple processes allowing an unprivileged process to maintain a mapping after it is freed, allowing the process to read private data belonging to other processes or the kernel.

Frequently asked questions

What is CVE-2021-29626?
In FreeBSD 13.0-STABLE before n245117, 12.2-STABLE before r369551, 11.4-STABLE before r369559, 13.0-RC5 before p1, 12.2-RELEASE before p6, and 11.4-RELEASE before p9, copy-on-write logic failed to invalidate shared memory page mappings between multiple processes allowing an unprivileged process to maintain a mapping after it is freed, allowing the process to read private data belonging to other processes or the kernel.
How severe is CVE-2021-29626?
CVE-2021-29626 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-29626 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-29626?
CVE-2021-29626 primarily affects Freebsd. In total, 22 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-29626?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-29626 published?
CVE-2021-29626 was published on 2021-04-07 and last updated on 2026-06-17.

References

Affected products (22)

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