HIGHVulnerability

CVE-2026-85091

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.

Properties

severity
HIGH
score
7.4
epss_score
0.00442
cve_id
CVE-2026-85091
signal_observed_at
2026-09-15T21:12:51+00:00
vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H
published_at
2026-09-03T13:06:20.573
last_modified
2026-09-09T20:41:07.123
epss_percentile
0.37443

Related Entities (3)

ENRICHED_BY (1)

[Source]FIRST EPSS

HAS_WEAKNESS (1)

[Weakness]Out-of-bounds Write

DESCRIBED_BY (1)

[Source]NVD

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CVE-2026-85091 — Ninja Signal Threat Intelligence | Ninja Signal