CVE-2026-41921: Koha Stored XSS via Purchase Suggestion Handler

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-18 · updated 2026-10-22
Weakness: CWE-79

Description

Koha before 26.05.02, 25.11.07, and 25.05.13 contains a stored cross-site scripting vulnerability in the purchase suggestion handler that allows authenticated staff users to inject malicious scripts by submitting unsanitized input through the suggestion save operation. Attackers can supply crafted HTML or script content in fields such as title, author, isbn, publishercode, place, collectiontitle, itemtype, and note, which are stored without sanitization and later rendered in the suggestion list template, causing injected scripts to execute in the browser of any staff user who views the suggestions.

Affected products

Koha Community Koha: from 26.05.0 before 26.05.02; from 25.11.0 before 25.11.07; from 25.05.0 before 25.05.13 — fixed in 25.05.13, 25.11.07, 26.05.02

How to fix

Upgrade to a fixed version: Koha Community Koha 25.05.13, 25.11.07, 26.05.02. Check the vendor advisory for mitigations.

References

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