Reference page — cumulative record through Saturday, October 3, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
AV AC AT PR UI VC VI VA CVSS EPSS %ile KEV N H N N N N H H 8.3 .0059 46.4 —
AFFECTED Product Versions Fixed zlib 1.2.11 – —
TIMELINE Aug 19 Reserved by VulnCheck Aug 24 Published (CNA: VulnCheck) Sep 30 EXPLOIT PUBLISHED — CVE-2026-76844 (zlib). Public exploit reference added.
zlib 1.2.11 through 1.3.2 contains a heap buffer overflow: after an underlying write() fails, gz_write() returns without resetting strm.next_in, leaving it pointed at the caller's buffer. A later gz* write call then derives a position from the stale pointer and writes past a heap allocation; any write() failure reaches it, including EPIPE on a blocking descriptor, and in versions before 1.3.1.2 the failed write must be followed by a gzclearerr() call.
| Date | Event | Detail |
|---|---|---|
| August 19, 2026 | Reserved | Reserved by VulnCheck |
| August 24, 2026 | Published | Published (CNA: VulnCheck) |
| September 30, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-76844 (zlib). Public exploit reference added. |
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
|---|---|---|---|---|
| zlib | zlib | — | 1.2.11 | — |
Authoritative record: CVE-2026-76844 at cve.org
Vendors: zlib
Weaknesses: CWE-787
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-76844 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Saturday, October 3, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.
