CVE-2026-117556Published

zchunk before 1.5.5 Heap Out-of-Bounds Read via read_preface()

Exact source revision recorded 27 Oct 2026 15:09:21 UTC. It does not establish the source's current position. Latest evidence.

Recorded JSON

cve-program · CVE-2026-117556

Published

zchunk before 1.5.5 contains a heap out-of-bounds read vulnerability in read_preface() in src/lib/header.c that passes the total header length instead of remaining bytes to compint parsing functions. Attackers can supply a crafted .zck file whose header ends inside a compressed integer, causing reads past the heap header buffer and crashing the application.

Source published: 27 Oct 2026 13:07:51 UTC
Source modified: 27 Oct 2026 13:07:51 UTC
Observed here: 27 Oct 2026 15:09:21 UTC
Source terms: CVE Program Terms of Use

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 4.0 · 5.3 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

CVSS 3.1 · 4.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L