zlib 1.2.11 through 1.3.2 Heap Buffer Overflow via Stale gzwrite Pointer After Failed Write
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.
CVE-2026-76844
Primary source · Revision 2
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-76844
zlib
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"vendor": "zlib",
"product": "zlib",
"versions": [
{
"status": "affected",
"version": "1.2.11",
"versionType": "custom",
"lessThanOrEqual": "1.3.2"
}
],
"packageURL": "pkg:github/madler/zlib",
"defaultStatus": "unaffected"
}
]- Related CVEs
- CVE-2026-76844
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #72824 · Revision 2
- Added to Heist Feed
- Publisher date