CVE-2026-85091: high-severity vulnerability in zlib
zlib 1.3.1.2 through 1.3.2 Heap Buffer Overflow via gz_vacate
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
41Vexday Risk Score
No sign of exploitation. It has a public proof of concept.
ssvc Attendcvss 8.3epss 0.5%
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.
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N
Affected products
zlib · zlibpublic PoCs found — 1
cve_referencegist.github.com/thesmartshadow/e0b9481792afb7c31e86fee1ff084490unverified⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
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