What is CVE-2026-123857?

CVE-2026-123857 is a medium-severity vulnerability in Jetbrains Phpstorm, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 4.3/10. Published 2026-11-06.

How severe is CVE-2026-123857?

Medium severity. CVSS v3 base score is 4.3 out of 10.

XXE in Jetbrains Phpstorm

CVE-2026-123857

In JetBrains PhpStorm before 2026.3 xXE was possible in untrusted projects via PHPMD ruleset autodetection

Vulnerability class: XXE (XML External Entity)

Published 2026-11-06 · last modified 2026-11-06.

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Jetbrains Phpstorm

Weakness classification (CWE)

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

References

www.jetbrains.com/privacy-security/issues-fixed/

Frequently asked questions

What is CVE-2026-123857?: CVE-2026-123857 is a medium-severity vulnerability in Jetbrains Phpstorm, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 4.3/10. Published 2026-11-06.
How severe is CVE-2026-123857?: Medium severity. CVSS v3 base score is 4.3 out of 10.