Vulnerability-Lookup

GHSA-QJRJ-QXX7-FC4J

Vulnerability from github – Published: 2026-08-20 15:34 – Updated: 2026-08-20 15:34

Details

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.

Severity

8.4 (High)


                  
                    CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

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{
  "affected": [],
  "aliases": [
    "CVE-2026-77118"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-787"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-20T13:19:07Z",
    "severity": "HIGH"
  },
  "details": "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.\n\n\n\nA 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 \u2014 for example with gm convert or gm identify, or through any application linked against libGraphicsMagick \u2014 can corrupt heap memory beyond the buffers.",
  "id": "GHSA-qjrj-qxx7-fc4j",
  "modified": "2026-08-20T15:34:17Z",
  "published": "2026-08-20T15:34:17Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-77118"
    },
    {
      "type": "WEB",
      "url": "https://foss.heptapod.net/graphicsmagick/graphicsmagick/-/commit/937cdd9920bd96"
    },
    {
      "type": "WEB",
      "url": "https://foss.heptapod.net/graphicsmagick/graphicsmagick/-/raw/GraphicsMagick-1_3_48/ChangeLog"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-77118 (GCVE-0-2026-77118)

Vulnerability from cvelistv5 – Published: 2026-08-20 12:42 – Updated: 2026-08-20 12:56

Title

Out-of-bounds write in GraphicsMagick PCD decoder

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.

Severity

8.4 (High)


                        
                          CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

CWE

CWE-787 - Out-of-bounds write

Assigner

seal mitre root

References

2 references

URL	Tags
https://foss.heptapod.net/graphicsmagick/graphics…	patch
https://foss.heptapod.net/graphicsmagick/graphics…	release-notes

Impacted products

3 products

Vendor	Product	Version
GraphicsMagick Group	GraphicsMagick	Affected: 1.0.0 , < 1.3.48 (semver) cpe:2.3:a:graphicsmagick:graphicsmagick::::::::
Debian	graphicsmagick	Affected: 0 , < 1.4+really1.3.48-1 (deb) cpe:2.3:o:debian:debian_linux:11:::::::* cpe:2.3:o:debian:debian_linux:12:::::::* cpe:2.3:o:debian:debian_linux:13:::::::*
Fedora Project	GraphicsMagick	Affected: 0 , < 1.3.48 (rpm) cpe:2.3:a:fedoraproject:extra_packages_for_enterprise_linux:8.0:::::::* cpe:2.3:a:fedoraproject:extra_packages_for_enterprise_linux:9.0:::::::*

Date Public

2026-08-20 09:43

Credits

Cipher - Causal Security (https://causalsecurity.com/), who discovered the defect and reported it to the GraphicsMagick maintainer on 2026-06-14 Bob Friesenhahn, GraphicsMagick, for the upstream fix

Show details on NVD website

JSON

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "cpes": [
            "cpe:2.3:a:graphicsmagick:graphicsmagick:*:*:*:*:*:*:*:*"
          ],
          "defaultStatus": "unaffected",
          "modules": [
            "PCD / PCDS image coder"
          ],
          "platforms": [
            "Linux",
            "Windows",
            "macOS"
          ],
          "product": "GraphicsMagick",
          "programFiles": [
            "coders/pcd.c"
          ],
          "programRoutines": [
            {
              "name": "DecodeImage"
            }
          ],
          "repo": "https://foss.heptapod.net/graphicsmagick/graphicsmagick",
          "vendor": "GraphicsMagick Group",
          "versions": [
            {
              "lessThan": "1.3.48",
              "status": "affected",
              "version": "1.0.0",
              "versionType": "semver"
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          ]
        },
        {
          "collectionURL": "https://packages.debian.org",
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            "cpe:2.3:o:debian:debian_linux:11:*:*:*:*:*:*:*",
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            "cpe:2.3:o:debian:debian_linux:13:*:*:*:*:*:*:*"
          ],
          "defaultStatus": "unaffected",
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              "lessThan": "1.4+really1.3.48-1",
              "status": "affected",
              "version": "0",
              "versionType": "deb"
            }
          ]
        },
        {
          "collectionURL": "https://dl.fedoraproject.org/pub/epel",
          "cpes": [
            "cpe:2.3:a:fedoraproject:extra_packages_for_enterprise_linux:8.0:*:*:*:*:*:*:*",
            "cpe:2.3:a:fedoraproject:extra_packages_for_enterprise_linux:9.0:*:*:*:*:*:*:*"
          ],
          "defaultStatus": "unaffected",
          "packageName": "GraphicsMagick",
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              "status": "affected",
              "version": "0",
              "versionType": "rpm"
            }
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          "nodes": [
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              "cpeMatch": [
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                  "criteria": "cpe:2.3:a:graphicsmagick:graphicsmagick:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "1.3.48",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            },
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:debian:debian_linux:11:*:*:*:*:*:*:*",
                  "vulnerable": true
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                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:debian:debian_linux:13:*:*:*:*:*:*:*",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:a:fedoraproject:extra_packages_for_enterprise_linux:8.0:*:*:*:*:*:*:*",
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                },
                {
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      ],
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          "capecId": "CAPEC-100",
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        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
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            "Recovery": "NOT_DEFINED",
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            "attackComplexity": "LOW",
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            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
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            "subConfidentialityImpact": "NONE",
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            {
              "base64": false,
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              "value": "\u003cp\u003eWhere upgrading is not possible, prevent the PCD and PCDS coders from being used on untrusted input. GraphicsMagick detects PCD by file content, so filtering on filename extension is not sufficient; the coder module must be removed or the format rejected before decoding.\u003c/p\u003e"
            }
          ],
          "value": "Where upgrading is not possible, prevent the PCD and PCDS coders from being used on untrusted input. GraphicsMagick detects PCD by file content, so filtering on filename extension is not sufficient; the coder module must be removed or the format rejected before decoding."
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    "assignerOrgId": "22e2d327-25fe-45d7-9f0c-dcd23b7108df",
    "assignerShortName": "seal",
    "cveId": "CVE-2026-77118",
    "datePublished": "2026-08-20T12:42:42.952Z",
    "dateReserved": "2026-08-20T12:40:51.495Z",
    "dateUpdated": "2026-08-20T12:56:01.246Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

GHSA-QJRJ-QXX7-FC4J

CVE-2026-77118 (GCVE-0-2026-77118)

Tags

Sightings

Nomenclature