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Fencer Intel
low 3.3

CVE-2026-47712 json

Dulwich doesn't sanitize commit subjects in `porcelain.format_patch`

published 5mo ago modified 3mo ago also EUVD-2026-36186 , GHSA-555p-6grf-mh7f , PYSEC-2026-2462

cvss
3.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.1%
EPSS 0.1% chance of exploitation in 30 days, percentile 3%
public exploits
0
none known

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.porcelain.format_patch(outdir=...) derives each patch filename from the commit's subject line. Prior to this fix, get_summary only replaced spaces with dashes - path separators (/, \), parent-directory components (..), and other filename-hostile characters (e.g. :) were preserved verbatim and passed straight into os.path.join(outdir, f"{i:04d}-{summary}.patch"). A malicious commit subject could therefore direct the generated patch file outside the requested outdir. This is fixed in Dulwich 1.2.5. Users should upgrade to 1.2.5 or later. dulwich.patch.get_summary now mirrors git's format_sanitized_subject: only `[A-Za-z0-9._]` are kept, runs of other characters collapse to a single -, consecutive . collapse to a single ., trailing ./- are stripped, and the result is length-limited. This makes the returned string safe to embed as a filename component, so format_patch can no longer be steered out of outdir via the commit subject. Until upgrading, callers that pass untrusted commits to porcelain.format_patch can use stdout=True and write the patch to a destination they control, rather than letting format_patch choose the filename; validate the chosen path before opening - e.g. compare os.path.realpath(returned_path) against os.path.realpath(outdir) and reject any patch whose resolved path is not inside outdir; and/or pre-screen commits and refuse to format any whose subject's first line contains /, \, .., or other characters that are not safe on the target filesystem.

Patch / fix

  • pypi dulwich 1.2.5
  • dulwich_project dulwich 1.2.5
  • dulwich Debian 14 1.2.5-1

debian advisories DEBIAN-CVE-2026-47712

  • python-dulwich openSUSE Tumbleweed 1.2.5-1.1

opensuse advisories openSUSE-SU-2026:10900-1

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-47712 updated cvss 3.3

dulwich: Dulwich: Arbitrary file write via malicious commit subject in format_patch

  • Red Hat Ansible Automation Platform 2 ansible-automation-platform-26/controller-rhel9, ansible-automation-platform-27/controller-rhel9, ansible-automation-platform-26/eda-controller-rhel9, ansible-automation-platform-27/eda-controller-rhel9, ansible-automation-platform-26/lightspeed-chatbot-rhel9 Red Hat Enterprise Linux 7 resource-agents, resource-agents-gcp, resource-agents-sap, sap-cluster-connector, resource-agents-aliyun, resource-agents-sap-hana, +1 more Red Hat Enterprise Linux 8 resource-agents, resource-agents-gcp, resource-agents-paf, resource-agents-aliyun Red Hat OpenShift AI (RHOAI) rhoai/odh-kserve-agent-rhel9, rhoai/odh-kserve-router-rhel9, rhoai/odh-kserve-controller-rhel9, rhoai/odh-kserve-autogluon-server-rhel9, rhoai/odh-kserve-storage-initializer-rhel9 Red Hat OpenShift Container Platform 4 python-dulwich Red Hat Satellite 6 python-dulwich
    affected: workaround, no fix available “Fix deferred”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
5mo ago

Exploit prediction

0.14% chance of exploitation in the next 30 days, higher than 3% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 3.1 3.3 CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
GitHub 3.1 3.3 CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
OSV 3.1 3.3 CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N

Affected packages

ecosystem package affected fixed in
pypi dulwich
>=0.24.0, <1.2.5
1.2.5

Affected products

  • jelmer dulwich

Classification

Weakness
  • CWE-22 Improper Limitation of a Pathname to a Restricted Directory

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

The maintainers of jelmer/dulwich published their own advisory on GitHub. Reviewed sources take precedence over it.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.