CVE-2023-6378 — logback-classic
HIGHCVE-2023-6378 is a high-severity (CVSS 7.1) Deserialization of Untrusted Data vulnerability in ch.qos.logback:logback-classic. A fix is available for ch.qos.logback:logback-classic — see the affected versions and patch details below.
Logback "receiver" DOS vulnerability
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-6378.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2023-6378 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,333 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
ch.qos.logback:logback-classic☕ch.qos.logback:logback-classic☕ch.qos.logback:logback-core☕ch.qos.logback:logback-core☕ch.qos.logback:logback-core☕ch.qos.logback:logback-classicReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
A serialization vulnerability in logback receiver component part of logback version 1.4.11 allows an attacker to mount a Denial-Of-Service attack by sending poisoned data.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | ch.qos.logback:logback-classic | ≥ 1.3.0&&< 1.3.12 | 1.3.12ch.qos.logback:logback-classic:1.3.12 |
| ☕Maven | ch.qos.logback:logback-classic | ≥ 1.4.0&&< 1.4.12 | 1.4.12ch.qos.logback:logback-classic:1.4.12 |
| ☕Maven | ch.qos.logback:logback-core | ≥ 1.3.0&&< 1.3.12 | 1.3.12ch.qos.logback:logback-core:1.3.12 |
| ☕Maven | ch.qos.logback:logback-core | ≥ 1.4.0&&< 1.4.12 | 1.4.12ch.qos.logback:logback-core:1.4.12 |
| ☕Maven | ch.qos.logback:logback-core | all versions | 1.2.13ch.qos.logback:logback-core:1.2.13 |
| ☕Maven | ch.qos.logback:logback-classic | all versions | 1.2.13ch.qos.logback:logback-classic:1.2.13 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ch.qos.logback:logback-classic, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update ch.qos.logback:logback-classic to 1.3.12 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-6378 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2023-6378 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2023-6378. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
The Logback package vulnerability, posing a risk of denial-of-service through a serialization flaw in its receiver component, is considered a moderate issue due to its potential impact on system availability. While denial-of-service vulnerabilities can be disruptive, the severity is tempered by the fact that they…
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat AMQ Broker 7 | logback | RHSA-2024:2945 |
| Red Hat Fuse 7.13.0 | logback | RHSA-2024:3354 |
| Red Hat OpenShift Dev Spaces 3 Containers | devspaces/server-rhel8:3.15-3 | RHSA-2024:4631 |
| RHINT Camel-Springboot 4.0.3 | logback | RHSA-2024:0793 |
Frequently Asked Questions
Is CVE-2023-6378 in your dependencies?
O3 Security finds CVE-2023-6378 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.