What is CVE-2026-51080?

CVE-2026-51080 is a critical-severity vulnerability in Proxmox Libpve-Storage-Perl, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 9.8/10. Published 2026-07-17.

How severe is CVE-2026-51080?

Critical severity. CVSS v3 base score is 9.8 out of 10.

XXE in Proxmox Libpve-Storage-Perl

CVE-2026-51080

libpvestorage-perl v9.1.1 and libpve-storage-perl v8.3.7 were discovered to contain an XML External Entity (XXE) vulnerability.

Vulnerability class: XXE (XML External Entity)

Published 2026-07-17 · last modified 2026-08-11.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.005 (43.1th percentile), scored 2026-10-22.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 43rd percentile — 43.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Proxmox Libpve-Storage-Perl — versions 8.3.7, 9.1.1

Weakness classification (CWE)

CWE-611 — Improper Restriction of XML External Entity Reference (XXE)

References

forum.proxmox.com/threads/proxmox-virtual-environment-security-advisories.14933… (Issue Tracking, Vendor Advisory)

Frequently asked questions

What is CVE-2026-51080?: CVE-2026-51080 is a critical-severity vulnerability in Proxmox Libpve-Storage-Perl, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 9.8/10. Published 2026-07-17.
How severe is CVE-2026-51080?: Critical severity. CVSS v3 base score is 9.8 out of 10.