Out-of-bounds Write Affecting zlib-1.2.11 package, versions <1.2.11+e1


Severity

Recommended
0.0
high
0
10

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Threat Intelligence

EPSS
0.59% (47th percentile)

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  • Snyk IDSNYK-ECHOLATEST-ZLIB1211-20969840
  • published15 Oct 2026
  • disclosed24 Aug 2026

Introduced: 24 Aug 2026

CVE-2026-76844  (opens in a new tab)
CWE-787  (opens in a new tab)

How to fix?

Upgrade Echo:latest zlib-1.2.11 to version 1.2.11+e1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream zlib-1.2.11 package and not the zlib-1.2.11 package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1