CVE-2025-71263
CVSS Score
7.4
EPSS Score
0.0%
EPSS Percentile
3th
In UNIX Fourth Research Edition (v4), the su command is vulnerable to a buffer overflow due to the 'password' variable having a fixed size of 100 bytes. A local user can exploit this to gain root privileges. It is unlikely that UNIX v4 is running anywhere outside of a very small number of lab environments. NOTE: This vulnerability only affects products that are no longer supported by the maintainer.
| CWE | CWE-120 |
| Vendor | at&t bell labs |
| Product | unix |
| Published | Mar 13, 2026 |
| Last Updated | Mar 21, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H Attack Vector
Local
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Affected Versions
AT&T Bell Labs / UNIX
4
References
sigma-star.at: https://sigma-star.at/blog/2025/12/unix-v4-buffer-overflow/ tuhs.org: https://www.tuhs.org/pipermail/tuhs/2026-January/032991.html discuss.systems: https://discuss.systems/@ricci/115747843169814700 spinellis.gr: https://www.spinellis.gr/blog/20251223/ openwall.com: http://www.openwall.com/lists/oss-security/2026/03/20/6 openwall.com: http://www.openwall.com/lists/oss-security/2026/03/21/4