Logback deserialization whitelist bypass for Proxy objects (QOS.CH Sarl logback)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.37 % · percentile 31 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- NCSC.ch
- NVD status
- Deferred
Description
Deserialization of untrusted data vulnerability in QOS.CH Sarl logback logback-core (HardenedObjectInputStream (logback-core) modules) allows Object Injection, albeit heavily restricted. More precisely, an attacker able to influence serialized data sent to SimpleSocketServer or SimpleSSLSocketServer can instantiate Proxy objects. Although deserialization is heavily restricted by HardenedObjectInputStream and no practical way to achieve remote code execution or significant privilege escalation has been identified, this issue constitutes a bypass of the intended security restrictions. This issue affects logback: through 1.5.33 inclusive.
Weaknesses (CWE)
- CWE-502 — Deserialization of Untrusted Data
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 4.0 | LOW 2.9 | CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:P/RE:M/U:Green | NCSC.ch |
| CVSS 4.0 | LOW 2.9 | CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:M/U:Green | NVD · vulnerability@ncsc.ch (Secondary) |
Advisories
- GHSA-jhq6-gfmj-v8fx — Logback vulnerable to Object Injection through HardenedObjectInputStream modules
European references
- ENISA EUVD · EUVD-2026-33632
- GCVE · GCVE-0-2026-10532
CERT-FR advisories
- CERTFR-2026-AVI-1385 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1165 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr
Affected products
| Product | Versions |
|---|---|
| QOS.CH Sarl · logback | affected 0 ≤ 1.5.33 ; unaffected 1.5.34 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |