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TI-2026-78709 Aliases CVE-2026-114096

Symlink following in Dulwich checkout allows arbitrary file writes

Priority HIGH 67CWE-59Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
Passive
Attack complexity
Low
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 2 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat.

Summary

Dulwich from 0.24.0 before 1.2.8 follows symlinks during porcelain.checkout with explicit paths, because it opens files without refusing symlinks (CWE-59). A local attacker who can supply a crafted repository can make a checkout write arbitrary files, including a Git hook that runs code. The attack requires a user to run the checkout operation.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

Dulwich from 0.24.0 before 1.2.8 contains a symlink following vulnerability in porcelain.checkout(paths=[...]) that allows attackers to write arbitrary files by abusing raw os.open without O_NOFOLLOW. Attackers can craft a repository where a worktree symlink points to .git/hooks/post-checkout, so restoring the file from a tag writes a malicious hook for code execution.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00155 4th percentileScored 2026-11-07
Fix Partial dulwich (jelmer): 1.2.8Red Hat: 2 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
jelmerdulwich0.24.0 to before 1.2.81.2.8Patch availableCNA
  • dulwich Vendorjelmer Affected 0.24.0 to before 1.2.8 Fixed in 1.2.8 Patch available CNA

Remediation

Upgrade Dulwich to version 1.2.8. Red Hat rates this as Important and lists Red Hat Ansible Automation Platform 2 and Red Hat OpenShift AI (RHOAI) as affected, with no fix plan available.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA dulwich (jelmer) Fixed in 1.2.8

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    jelmer dulwich 1.2.8

    3 records Highest priority Priority HIGH 1 HIGH, 2 LOW

    Other records, highest priority first

    • TI-2026-78711 Dulwich Path Traversal via Stash Pop SymlinksPriority LOW 33
    • TI-2026-78710 Symlink path traversal in Dulwich filter_branch enables file writesPriority LOW 33
    Show all 3 records →

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Ansible Automation Platform 2AffectedNo fix yet
Red Hat OpenShift AI (RHOAI)AffectedNo fix yet
Not affected: 5 products
  • Red Hat Ansible Automation Platform 2
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat OpenShift AI (RHOAI)
  • Red Hat OpenShift Container Platform 4

Timeline

  1. 2026-10-21 Threatist record created from CVE-2026-114096
  2. 2026-10-21 Affected versions changed · Red Hat
  3. 2026-10-21 CVSS score added · Red Hat
  4. 2026-10-22 Priority changed: MEDIUM → LOW
  5. 2026-10-28 CISA SSVC decision points changed
  6. 2026-10-28 Priority changed: LOW → HIGH

References

Advisory 1

  • TI-2026-78707 Path traversal in Dulwich lets attackers write files on Windows CVSS 4.0HIGH 8.7
  • TI-2026-37846 Path traversal in jelmer dulwich CVSS 3.1HIGH 7.5
  • TI-2026-30843 Dulwich Vulnerable to Command Injection via Merge Driver Path CVSS 4.0HIGH 7.7
  • TI-2026-30613 Dulwich has an arbitrary file write via NTFS-hostile tree entries on Windows CVSS 3.1HIGH 8.8
  • TI-2026-85266 Dulwich commit parser picks the wrong tree from duplicate headers CVSS 4.0HIGH 8.6
  • TI-2026-78708 Infinite recursion in Dulwich pack parsing causes denial of service CVSS 4.0HIGH 7.1
See all 10 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences