Path Traversal in Simplesamlphp Simplesamlphp-Module-Casserver

CVE-2026-46491

SimpleSAMLphp-casserver is a CAS 1.0 and 2.0 compliant CAS server in the form of a SimpleSAMLphp module. Prior to version 7.0.3, simplesamlphp-module-casserver builds file paths for the file-based CAS ticket store by directly concatenating the configured ticket directory with an attacker-controlled ticket identifier. Public CAS validation/proxy endpoints pass attacker-controlled ticket / pgt query parameters into this store. In deployments using FileSystemTicketStore, a remote attacker can use path traversal sequences such as ../target.serialized to make the CAS server read and unserialize files outside the ticket directory. In the CAS 1.0 validation flow, the same attacker-selected path is also passed to deleteTicket() immediately after getTicket() returns, which can delete the target file when it is readable by the PHP process, deletable under the PHP process filesystem permissions, and unserializes to a value compatible with the ?array return type. This issue has been patched in version 7.0.3.

Vulnerability class: Path Traversal (Directory Traversal)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L.

EPSS exploit prediction

EPSS: 0.006 (47.7th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 48th percentile — 47.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-46491: held from 0.004 to 0.006.

EPSS over last 30 days · oldest: 0.004 · newest: 0.006 · change: +0.002

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-46491?
CVE-2026-46491 is a high-severity vulnerability in Simplesamlphp Simplesamlphp-Module-Casserver, classified under Path Traversal. CVSS score: 8.6/10. Published 2026-06-10.
How severe is CVE-2026-46491?
High severity. CVSS v3 base score is 8.6 out of 10.