CVSS 4.0
8.3 highCVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:NCVE-2026-85091
High (8.3). EPSS 0.5% chance of exploitation in the next 30 days.
zlib versions 1.3.1.2 through 1.3.2 contain a heap buffer overflow vulnerability in the gz_vacate() function when processing non-blocking gzwrite() operations with stale external buffer pointers. Attackers can trigger the overflow by calling gzprintf() or gzvprintf() after a write stall, causing an unchecked memmove() to write beyond the internal input buffer boundary.
Severity
CVSS 3.1
7.4 highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H- EPSS
- 0.5% chance of exploitation in the next 30 days; higher than 40% of CVEs (scores of 2026-10-31)
- CWE
- CWE-787
- Published
- Modified
- Record from
- the NVD, synced