vulnerability
FreeBSD: VID-A9C6E9BE-61FB-11EB-B87A-901B0EF719AB (CVE-2020-25579): FreeBSD -- Uninitialized kernel stack leaks in several file systems
Severity | CVSS | Published | Added | Modified |
---|---|---|---|---|
5 | (AV:N/AC:L/Au:N/C:P/I:N/A:N) | 2021-01-29 | 2021-01-30 | 2021-04-05 |
Description
Details for this vulnerability have not been published by NIST at this point. Descriptions from software vendor advisories for this issue are provided below.
From VID-A9C6E9BE-61FB-11EB-B87A-901B0EF719AB:
Problem Description:
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. This problem is not present in
FreeBSD 11.
Additionally, msdosfs(5) was failing to zero-fill a pair of padding
fields in the dirent structure, resulting in a leak of three
uninitialized bytes.
Impact:
Kernel stack disclosures may leak sensitive information which could
be used to compromise the security of the system.
Solution(s)
References

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