Koha versions up to 25.11 contain a Server-Side Request Forgery (SSRF) vulnerability via the Z39.50/SRU server configuration.

published 2026-06-03 5mo ago modified 2026-07-22 3mo ago also EUVD-2026-34170

cvss: 6.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 15%
public exploits: 0; none known

Koha versions up to 25.11 contain a Server-Side Request Forgery (SSRF) vulnerability via the Z39.50/SRU server configuration. This allows authenticated attackers to perform internal network scanning and identify running services by analyzing server response times.

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CISA SSVC

Exploitation: Proof of concept is public
Automatable: yes
Technical impact: total
Assessed: 5mo ago (2026-06-04)

Exploit prediction

0.24% chance of exploitation in the next 30 days, higher than 15% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

g03m0n.github.io https://g03m0n.github.io/posts/cve-2026-26379/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CISA ADP	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
CNA	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Classification

Weakness

CWE-918 Server-Side Request Forgery

References

g03m0n.github.io /posts/cve-2026-26379/
exploit, third-party-advisory
github.com /Koha-Community/Koha
product
g03m0n.github.io /
third-party-advisory

Sources

CVE List CVE-2026-26379
NVD CVE-2026-26379

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