Auth bypass in Chyrplite Chyrp Lite
CVE-2026-35173
Chyrp Lite is an ultra-lightweight blogging engine. Prior to 2026.01, an IDOR / Mass Assignment issue exists in the Post model that allows authenticated users with post editing permissions (Edit Post, Edit Draft, Edit Own Post, Edit Own Draft) to modify posts they do not own and do not have permission to edit. By passing internal class properties such as id into the post_attributes payload, an attacker can alter the object being instantiated. As a result, further actions are performed on another user’s post rather than the attacker’s own post, effectively enabling post takeover. This vulnerability is fixed in 2026.01.
Vulnerability class: IDOR (Insecure Direct Object Reference)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N.
EPSS exploit prediction
EPSS: 0.003 (21.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 21st percentile — 21.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001
Affected products
- Chyrplite Chyrp Lite
- Xenocrat Chyrp-Lite — versions < 2026.01
Weakness classification (CWE)
References
- github.com/xenocrat/chyrp-lite/security/advisories/GHSA-8c3h-rh2j-fxr9 (Vendor Advisory)
Frequently asked questions
- What is CVE-2026-35173?
- CVE-2026-35173 is a medium-severity vulnerability in Chyrplite Chyrp Lite, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 6.5/10. Published 2026-04-06.
- How severe is CVE-2026-35173?
- Medium severity. CVSS v3 base score is 6.5 out of 10.