CVE-2026-77118 (GCVE-0-2026-77118)
Vulnerability from cvelistv5
Published
2026-08-20 12:42
Modified
2026-08-26 19:51
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-787 - Out-of-bounds write
Summary
A heap out-of-bounds write exists in the Photo CD (PCD) decoder of GraphicsMagick. In DecodeImage() (coders/pcd.c), the Huffman delta loop advances its output pointer with q++ after every decoded delta and never checks it against the end of the heap-allocated luma/chroma plane buffers. The pointer is repositioned only when a sync marker introduces a new plane/row; between sync markers the run length is bounded solely by the input.
A crafted PCD file that positions the pointer near the end of a plane and then supplies a long run of deltas with no intervening sync therefore walks the pointer past the end of the allocation and writes through it. Processing an untrusted PCD file — for example with gm convert or gm identify, or through any application linked against libGraphicsMagick — can corrupt heap memory beyond the buffers.
References
Impacted products
| Vendor | Product | Version | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| GraphicsMagick Group | GraphicsMagick |
Version: 1.0.0 ≤ cpe:2.3:a:graphicsmagick:graphicsmagick:*:*:*:*:*:*:*:* |
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|
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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