Description
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.
Metrics
CVSS 3.1 4.3/10
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:LWeakness enumeration
Affected software
| Vendor | Product | Versions |
|---|---|---|
| zchunk | zchunk | < 1.5.5 |
References
- https://github.com/zchunk/zchunk
- https://github.com/zchunk/zchunk/blob/1.5.4/src/lib/header.c#L167
- https://github.com/zchunk/zchunk/commit/02b371a64bf98245df97315d07c684a0ca5ea1df
- https://github.com/zchunk/zchunk/issues/119
- https://github.com/zchunk/zchunk/releases/tag/1.5.5
- https://www.vulncheck.com/advisories/zchunk-before-1.5.5-heap-out-of-bounds-read-via-read-preface
Timeline
- Published
- Oct 27, 2026
- Last modified
- Oct 28, 2026
- NVD status
- Deferred