Improper input validation in Fraillt Bitsery
CVE-2026-9521
A security vulnerability has been detected in fraillt bitsery up to 5.2.4. Affected is the function loadFromSharedState in the library include/bitsery/ext/std_smart_ptr.h. Such manipulation leads to improper validation of specified type of input. It is possible to launch the attack remotely. The exploit has been disclosed publicly and may be used. Upgrading to version 5.2.5 is able to address this issue. The name of the patch is 66d16516e24893bebc1c8af52bf2fe9ad0735061. Upgrading the affected component is advised.
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.3 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L.
EPSS exploit prediction
EPSS: 0.005 (43.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 43rd percentile — 43.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.005 · change: +0.001
Affected products
- Fraillt Bitsery — versions 5.2.0, 5.2.1, 5.2.2
Weakness classification (CWE)
References
- vuldb.com/vuln/365541 (technical-description, vdb-entry)
- vuldb.com/vuln/365541/cti (signature, permissions-required)
- vuldb.com/submit/814457 (third-party-advisory)
- gist.github.com/TrebledJ/750abc64a826f19dd2d6774724629b71 (exploit)
- github.com/fraillt/bitsery/blob/master/CHANGELOG.md (release-notes)
- github.com/fraillt/bitsery/commit/66d16516e24893bebc1c8af52bf2fe9ad0735061 (patch)
- github.com/fraillt/bitsery/releases/tag/v5.2.5 (patch)
- github.com/fraillt/bitsery/ (product)
Frequently asked questions
- What is CVE-2026-9521?
- CVE-2026-9521 is a high-severity vulnerability in Fraillt Bitsery, classified under Improper Input Validation. CVSS score: 7.3/10. Published 2026-05-26.
- How severe is CVE-2026-9521?
- High severity. CVSS v3 base score is 7.3 out of 10.