CVE-2020-25578

Name: CVE-2020-25578
Creator: NVD / NIST
Published: 2021-03-26T21:15:12.6+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.3/10EPSS 2.31%

Last modified Jun 17, 2026

CVE-2020-25578 is a medium-severity vulnerability rated 5.3/10 on the CVSS scale. 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. EPSS estimates a 2.31% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

5.3/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

EPSS Probability

2.31%

81.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-665

Affected Software

Vendor	Product	Versions
Freebsd	Freebsd	11.4
Freebsd	Freebsd	12.1
Freebsd	Freebsd	12.2

References

https://security.FreeBSD.org/advisories/FreeBSD-SA-21:01.fsdisclosure.ascVendor Advisory
https://security.netapp.com/advisory/ntap-20210423-0002/Third Party Advisory
https://security.FreeBSD.org/advisories/FreeBSD-SA-21:01.fsdisclosure.ascVendor Advisory
https://security.netapp.com/advisory/ntap-20210423-0002/Third Party Advisory

Timeline

Published: Mar 26, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-25578?

How severe is CVE-2020-25578?

CVE-2020-25578 has a CVSS score of 5.3/10 (MEDIUM severity). The EPSS model estimates a 2.31% probability of exploitation in the next 30 days.

How do I fix CVE-2020-25578?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-25578?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST