How to fix or mitigate EUVD-2026-52854?

Within 24 hours, inventory all development workstations, CI/CD pipeline runners, and build automation systems running PDM and identify which are on versions through 2.22.4. Within 7 days, upgrade all affected instances to PDM version 2.27.0 or later and perform a fresh dependency resolution to ensure clean package installation across all projects. Within 30 days, review build artifacts and deployment logs from the past 6 months for evidence of unexpected files in unexpected locations, and implement hash verification or code scanning of recent releases as a detective control.

EUVD-2026-52854

Q: What is the CVSS score of EUVD-2026-52854?

EUVD-2026-52854 has a CVSS 4.0 base score of 8.4 (High). CVSS vector: 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. EPSS exploitation probability: 0.0%.

| CVE-2026-47764 HIGH

Path Traversal (CWE-22)

2026-06-10 https://github.com/pdm-project/pdm

GHSA-78v8-vpjp-cjqh PYSEC-2026-2861

Path Traversal

8.4

CVSS 4.0 · Vendor: https://github.com/pdm-project/pdm

Severity by source

Vendor (https://github.com/pdm-project/pdm) PRIMARY

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/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

vuln.today AI

6.1 MEDIUM

Local install action (AV:L), no privileges needed but user must run pdm install on the malicious wheel (UI:R); arbitrary file write yields high integrity impact, no direct confidentiality loss, partial availability via overwrite.

3.1 AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:L

SUSE

MEDIUM

qualitative

Primary rating from Vendor (https://github.com/pdm-project/pdm).

CVSS VectorVendor: https://github.com/pdm-project/pdm

Attack Vector

Local

Attack Complexity

Low

Privileges Required

None

User Interaction

Scope

Lifecycle Timeline

Analysis Updated

Aug 04, 2026 - 19:30 vuln.today

v2 (cvss_changed)

Re-analysis Queued

Aug 04, 2026 - 19:22 vuln.today

cvss_changed

CVSS changed

Aug 04, 2026 - 19:22 NVD

8.4 (HIGH)

Source Code Evidence Fetched

Jun 10, 2026 - 21:19 vuln.today

Analysis Generated

Jun 10, 2026 - 21:19 vuln.today

DescriptionCVE.org

InstallDestination.write_to_fs() in src/pdm/installers/installers.py overrides the base class to add symlink/hardlink support but replaces the safe _path_with_destdir() (which validates via Path.resolve() + is_relative_to()) with a bare os.path.join() that performs no path validation. A malicious wheel with traversal entries can write arbitrary files. Same class as Poetry CVE-2026-34591. Fix ready at: https://github.com/pdm-project/pdm/pull/3787.

AnalysisAI

Arbitrary file write in PDM's wheel installer allows a maliciously crafted Python package to escape its designated installation directory and write attacker-controlled content anywhere on the target filesystem permitted by the running user's OS permissions. PDM versions through 2.22.4 are affected due to the InstallDestination.write_to_fs() override silently dropping the parent class's validated path resolution in favor of an unguarded os.path.join() call. No active exploitation is confirmed (not in CISA KEV, EPSS 0.05%), but the vulnerability class is well-understood, the fix is in released version 2.27.0, and the supply chain threat model makes developer workstations and CI/CD pipelines the primary exposure surface.