CVE-2020-25578

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-03-26 · updated 2026-06-17
Weakness: CWE-665

Description

In FreeBSD 12.2-STABLE before r368969, 11.4-STABLE before r369047, 12.2-RELEASE before p3, 12.1-RELEASE before p13 and 11.4-RELEASE before p7 several file systems were not properly initializing the d_off field of the dirent structures returned by VOP_READDIR. In particular, tmpfs(5), smbfs(5), autofs(5) and mqueuefs(5) were failing to do so. As a result, eight uninitialized kernel stack bytes may be leaked to userspace by these file systems.

Affected products

FreeBSD: 11.4, 11.4-p1, 11.4-p2, 11.4-p3, 11.4-p4, 11.4-p5 (+17)

References

https://security.FreeBSD.org/advisories/FreeBSD-SA-21:01.fsdisclosure.asc
https://security.netapp.com/advisory/ntap-20210423-0002/
https://security.FreeBSD.org/advisories/FreeBSD-SA-21:01.fsdisclosure.asc
https://security.netapp.com/advisory/ntap-20210423-0002/

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