Auth bypass in Spip
CVE-2026-72709
SPIP before version 4.4.18 contains a missing authorization vulnerability in sensitive actions under ecrire/action/ that allows unauthenticated attackers to invoke privileged actions by supplying only a valid CSRF nonce without any server-side permission check. Attackers can bypass template-level authorization guards through direct HTTP requests to invoke actions such as editer_auteur, enabling arbitrary account password rewrites including administrator accounts and resulting in full account takeover.
Vulnerability class: Broken Access Control
Published · last modified .
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: 0.007 (51.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 51st percentile — 51.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: 0.000
Affected products
Weakness classification (CWE)
References
- Researcher Blog (technical-description, exploit)
- Release Notes (release-notes, patch)
- www.vulncheck.com/advisories/spip-missing-authorization-via-ecrire-action-edite… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-72709?
- CVE-2026-72709 is a critical-severity vulnerability in Spip, classified under Missing Authorization. CVSS score: 9.8/10. Published 2026-09-11.
- How severe is CVE-2026-72709?
- Critical severity. CVSS v3 base score is 9.8 out of 10.