Heap Buffer Overread in util-linux setpwnam() (256-byte usernames)
CVE-2025-14104 Published on December 5, 2025
Util-linux: util-linux: heap buffer overread in setpwnam() when processing 256-byte usernames
A flaw was found in util-linux. This vulnerability allows a heap buffer overread when processing 256-byte usernames, specifically within the `setpwnam()` function, affecting SUID (Set User ID) login-utils utilities writing to the password database.
Vulnerability Analysis
CVE-2025-14104 is exploitable with local system access, and requires small amount of user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have a small impact on confidentiality, a small impact on integrity, and a high impact on availability.
Timeline
Reported to Red Hat.
Made public.
Weakness Type
Out-of-bounds Read
The software reads data past the end, or before the beginning, of the intended buffer. Typically, this can allow attackers to read sensitive information from other memory locations or cause a crash. A crash can occur when the code reads a variable amount of data and assumes that a sentinel exists to stop the read operation, such as a NUL in a string. The expected sentinel might not be located in the out-of-bounds memory, causing excessive data to be read, leading to a segmentation fault or a buffer overflow. The software may modify an index or perform pointer arithmetic that references a memory location that is outside of the boundaries of the buffer. A subsequent read operation then produces undefined or unexpected results.
Products Associated with CVE-2025-14104
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Affected Versions
util-linux:- Before 2.41.3 is affected.
- Version 0:2.40.2-15.el10_1 and below * is unaffected.
- Version 0:2.32.1-48.el8_10 and below * is unaffected.
- Version 0:2.32.1-48.el8_10 and below * is unaffected.
- Version 0:2.37.4-21.el9_7 and below * is unaffected.
- Version 0:2.37.4-21.el9_7 and below * is unaffected.
- Version 1770632724 and below * is unaffected.
- Version 1770630907 and below * is unaffected.
- Version 1771816028 and below * is unaffected.
- Version 2.42-7.1.hum1 and below * is unaffected.
- Version 1770740405 and below * is unaffected.
- Version 1770646925 and below * is unaffected.
- Version 1773670073 and below * is unaffected.
- Version 1773672059 and below * is unaffected.
- Version 1773670137 and below * is unaffected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.