Vulnerability-Lookup

UBUNTU-CVE-2026-42563 (CVE-2026-42563)

Vulnerability from osv_ubuntu – Published: 2026-06-10 23:16 – Updated: 2026-06-17 04:28 – Source website

Details

Dulwich is a pure-Python implementation of the Git file formats and protocols. Starting in version 0.24.0 and prior to version 1.2.5, Dulwich's ProcessMergeDriver substitutes the file path (from the git tree, controllable by an attacker via a malicious branch) into the merge driver command via the %P placeholder and executes it with subprocess.run(..., shell=True). An attacker who can cause a victim to merge an untrusted branch can achieve arbitrary command execution by crafting malicious file paths. Version 1.2.5 fixes the issue.

Severity

7.7 (High)


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

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-42563	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-42563	REPORT
	https://github.com/jelmer/dulwich/security/adviso…	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "pypy-dulwich",
            "binary_version": "0.12.0-1build2"
          },
          {
            "binary_name": "python-dulwich",
            "binary_version": "0.12.0-1build2"
          },
          {
            "binary_name": "python3-dulwich",
            "binary_version": "0.12.0-1build2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:16.04:LTS",
        "name": "dulwich",
        "purl": "pkg:deb/ubuntu/dulwich@0.12.0-1build2?arch=source\u0026distro=xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.11.2-1ubuntu1",
        "0.12.0-1",
        "0.12.0-1build1",
        "0.12.0-1build2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "pypy-dulwich",
            "binary_version": "0.18.5-1"
          },
          {
            "binary_name": "python-dulwich",
            "binary_version": "0.18.5-1"
          },
          {
            "binary_name": "python3-dulwich",
            "binary_version": "0.18.5-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "dulwich",
        "purl": "pkg:deb/ubuntu/dulwich@0.18.5-1?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.18.2-1build1",
        "0.18.5-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "pypy-dulwich",
            "binary_version": "0.19.15-1build1"
          },
          {
            "binary_name": "python3-dulwich",
            "binary_version": "0.19.15-1build1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "dulwich",
        "purl": "pkg:deb/ubuntu/dulwich@0.19.15-1build1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.19.11-2",
        "0.19.14-4ubuntu1",
        "0.19.15-1",
        "0.19.15-1build1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "python3-dulwich",
            "binary_version": "0.20.31-1.1build1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "dulwich",
        "purl": "pkg:deb/ubuntu/dulwich@0.20.31-1.1build1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.20.15-1ubuntu1",
        "0.20.31-1ubuntu1",
        "0.20.31-1.1",
        "0.20.31-1.1build1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "python3-dulwich",
            "binary_version": "0.21.6-1build2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "dulwich",
        "purl": "pkg:deb/ubuntu/dulwich@0.21.6-1build2?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.21.6-1",
        "0.21.6-1build1",
        "0.21.6-1build2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "python3-dulwich",
            "binary_version": "0.22.7-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "dulwich",
        "purl": "pkg:deb/ubuntu/dulwich@0.22.7-1?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.22.7-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "python3-dulwich",
            "binary_version": "1.1.0-3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "dulwich",
        "purl": "pkg:deb/ubuntu/dulwich@1.1.0-3?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.22.7-1",
        "0.24.2-2",
        "1.1.0-2ubuntu1",
        "1.1.0-3"
      ]
    }
  ],
  "aliases": [],
  "details": "Dulwich is a pure-Python implementation of the Git file formats and protocols. Starting in version 0.24.0 and prior to version 1.2.5, Dulwich\u0027s `ProcessMergeDriver` substitutes the file path (from the git tree, controllable by an attacker via a malicious branch) into the merge driver command via the `%P` placeholder and executes it with `subprocess.run(..., shell=True)`. An attacker who can cause a victim to merge an untrusted branch can achieve arbitrary command execution by crafting malicious file paths. Version 1.2.5 fixes the issue.",
  "id": "UBUNTU-CVE-2026-42563",
  "modified": "2026-06-17T04:28:53Z",
  "published": "2026-06-10T23:16:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-42563"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-42563"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/jelmer/dulwich/security/advisories/GHSA-9277-mp7x-85jf"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-42563"
  ]
}

CVE-2026-42563 (GCVE-0-2026-42563)

Vulnerability from cvelistv5 – Published: 2026-06-10 21:47 – Updated: 2026-06-12 03:55

Title

Dulwich Vulnerable to Command Injection via Merge Driver Path

Summary

Dulwich is a pure-Python implementation of the Git file formats and protocols. Starting in version 0.24.0 and prior to version 1.2.5, Dulwich's `ProcessMergeDriver` substitutes the file path (from the git tree, controllable by an attacker via a malicious branch) into the merge driver command via the `%P` placeholder and executes it with `subprocess.run(..., shell=True)`. An attacker who can cause a victim to merge an untrusted branch can achieve arbitrary command execution by crafting malicious file paths. Version 1.2.5 fixes the issue.

Severity

7.7 (High)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-11 00:00 UTC

CWE

CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

Assigner

GitHub_M mitre root

References

3 references

URL	Tags
https://github.com/jelmer/dulwich/security/adviso…	x_refsource_CONFIRM
https://github.com/jelmer/dulwich/commit/e3331b3b…	x_refsource_MISC
https://github.com/jelmer/dulwich/releases/tag/du…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
jelmer	dulwich	Affected: >= 0.24.0, < 1.2.5

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-42563",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-11T00:00:00+00:00",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-12T03:55:30.892Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/jelmer/dulwich/security/advisories/GHSA-9277-mp7x-85jf"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "dulwich",
          "vendor": "jelmer",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 0.24.0, \u003c 1.2.5"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Dulwich is a pure-Python implementation of the Git file formats and protocols. Starting in version 0.24.0 and prior to version 1.2.5, Dulwich\u0027s `ProcessMergeDriver` substitutes the file path (from the git tree, controllable by an attacker via a malicious branch) into the merge driver command via the `%P` placeholder and executes it with `subprocess.run(..., shell=True)`. An attacker who can cause a victim to merge an untrusted branch can achieve arbitrary command execution by crafting malicious file paths. Version 1.2.5 fixes the issue."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "baseScore": 7.7,
            "baseSeverity": "HIGH",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "PASSIVE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-78",
              "description": "CWE-78: Improper Neutralization of Special Elements used in an OS Command (\u0027OS Command Injection\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-10T21:47:14.927Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/jelmer/dulwich/security/advisories/GHSA-9277-mp7x-85jf",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/jelmer/dulwich/security/advisories/GHSA-9277-mp7x-85jf"
        },
        {
          "name": "https://github.com/jelmer/dulwich/commit/e3331b3b3a122fc313460182f928f59723580b7b",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/jelmer/dulwich/commit/e3331b3b3a122fc313460182f928f59723580b7b"
        },
        {
          "name": "https://github.com/jelmer/dulwich/releases/tag/dulwich-1.2.5",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/jelmer/dulwich/releases/tag/dulwich-1.2.5"
        }
      ],
      "source": {
        "advisory": "GHSA-9277-mp7x-85jf",
        "discovery": "UNKNOWN"
      },
      "title": "Dulwich Vulnerable to Command Injection via Merge Driver Path"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-42563",
    "datePublished": "2026-06-10T21:47:14.927Z",
    "dateReserved": "2026-04-28T17:26:12.083Z",
    "dateUpdated": "2026-06-12T03:55:30.892Z",
    "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.

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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

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UBUNTU-CVE-2026-42563 (CVE-2026-42563)

CVE-2026-42563 (GCVE-0-2026-42563)

Tags

Sightings

Nomenclature

Related by attack behaviour