01 Record
CVE-2025-71263
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
HighPUBLISHEDCNA: mitre
CNA base score7.4 CVSS v3.xCVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
02 Description
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
03 Exploitation and scoring
- Exploitation
- Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.
- SSVC decision
- ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
- AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
- Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.
- EPSS probability
- 0.18% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 8.1% of scored records. A rank, not a probability.
- NVD base score
- 7.8 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- NVD analysis status
- Analyzed. NVD last modified this record on 2026-06-17.
- Red Hat severity
- No Red Hat rating. Red Hat rates the CVEs that affect its products.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2026-03-13 18:38Z7 MO AGO
- Last updated
- 2026-03-21 22:00Z7 MO AGO
- Reserved
- 2026-03-13
- Assigning CNA
- mitre
- Record state
- PUBLISHED
- Severity
- High (CVSS 7.4)
- CNA CVSS vector
- CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- Weaknesses
- CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')Base
- Data version
- 5.2
- Document digest
- 8e04d721f45a3bf2e663d5d36b487fd9504d8f68467d4cd6893cb1400d11b1c6
05 Affected products
VendorProductVersionsPlatforms
06 References
- sigma-star.athttps://sigma-star.at/blog/2025/12/unix-v4-buffer-overflow/
- www.tuhs.orghttps://www.tuhs.org/pipermail/tuhs/2026-January/032991.html
- discuss.systemshttps://discuss.systems/@ricci/115747843169814700
- www.spinellis.grhttps://www.spinellis.gr/blog/20251223/
- www.openwall.comhttp://www.openwall.com/lists/oss-security/2026/03/20/6
- www.openwall.comhttp://www.openwall.com/lists/oss-security/2026/03/21/4