Review reviewHigh

CVE-2026-52726

jelmer dulwich

Dulwich is a pure-Python implementation of the Git file formats and protocols. Starting in version 0.23.2 and prior to version 1.2.5, `dulwich.porcelain.submodule_update`, and by extension `porcelain.clone(..., recurse_submodules=True)`, materializes attacker-controlled submodule paths from a crafted upstream repository without path validation. A malicious `.gitmodules` plus a matching tree gitlink whose `path` is `.git/hooks` (or any other directory inside the parent repository's `.git` directory) causes the attacker's submodule tree contents to be written directly into the victim's `.git/...

CVSS
7.5
EPSS
0.45%
36.7% percentile
CISA KEV
Not listed
Published
2026.06.11
PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability0.45%
Technical severityCVSS 7.5

Vulnerability overview

Dulwich is a pure-Python implementation of the Git file formats and protocols. Starting in version 0.23.2 and prior to version 1.2.5, `dulwich.porcelain.submodule_update`, and by extension `porcelain.clone(..., recurse_submodules=True)`, materializes attacker-controlled submodule paths from a crafted upstream repository without path validation. A malicious `.gitmodules` plus a matching tree gitlink whose `path` is `.git/hooks` (or any other directory inside the parent repository's `.git` directory) causes the attacker's submodule tree contents to be written directly into the victim's `.git/...

Affected product and versions

Product
jelmer dulwich
Affected versions
>= >= 0.23.2, < 1.2.5
Fixed versions
No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that jelmer dulwich and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
CWE-22
CVE-2026-52726 — jelmer dulwich | SECUFOCUS NOW