CVE-2023-42795 is a medium-severity (CVSS 5.3) vulnerability in org.apache.tomcat:tomcat. A fix is available for org.apache.tomcat:tomcat — see the affected versions and patch details below.
Apache Tomcat: Failure during request clean-up leads to sensitive data leaking to subsequent requests
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- 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-2023-42795.
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-2023-42795 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 378,567 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
org.apache.tomcat:tomcat☕org.apache.tomcat:tomcat☕org.apache.tomcat:tomcat☕org.apache.tomcat:tomcat☕org.apache.tomcat.embed:tomcat-embed-core☕org.apache.tomcat.embed:tomcat-embed-core☕org.apache.tomcat.embed:tomcat-embed-core☕org.apache.tomcat.embed:tomcat-embed-core+8 moreReal-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
Incomplete Cleanup vulnerability in Apache Tomcat.
When recycling various internal objects in Apache Tomcat from 11.0.0-M1 through 11.0.0-M11, from 10.1.0-M1 through 10.1.13, from 9.0.0-M1 through 9.0.80 and from 8.5.0 through 8.5.93, an error could cause Tomcat to skip some parts of the recycling process leading to information leaking from the current request/response to the next. Older, EOL versions may also be affected.
Users are recommended to upgrade to version 11.0.0-M12 onwards, 10.1.14 onwards, 9.0.81 onwards or 8.5.94 onwards, which fixes the issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.apache.tomcat:tomcat | ≥ 11.0.0-M1&&< 11.0.0-M12 | 11.0.0-M12org.apache.tomcat:tomcat:11.0.0-M12 |
| ☕Maven | org.apache.tomcat:tomcat | ≥ 10.1.0-M1&&< 10.1.14 | 10.1.14org.apache.tomcat:tomcat:10.1.14 |
| ☕Maven | org.apache.tomcat:tomcat | ≥ 9.0.0-M1&&< 9.0.81 | 9.0.81org.apache.tomcat:tomcat:9.0.81 |
| ☕Maven | org.apache.tomcat:tomcat | ≥ 8.5.0&&< 8.5.94 | 8.5.94org.apache.tomcat:tomcat:8.5.94 |
| ☕Maven | org.apache.tomcat.embed:tomcat-embed-core | ≥ 10.1.0-M1&&< 10.1.14 | 10.1.14org.apache.tomcat.embed:tomcat-embed-core:10.1.14 |
| ☕Maven | org.apache.tomcat.embed:tomcat-embed-core | ≥ 9.0.0-M1&&< 9.0.81 | 9.0.81org.apache.tomcat.embed:tomcat-embed-core:9.0.81 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.tomcat:tomcat, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.apache.tomcat:tomcat to 11.0.0-M12 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-42795 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-2023-42795 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2023-42795. 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.
Red Hat rates this as a Moderate impact as the confidentiality is not fully compromised and the malicious user does not have confirmation over the scenario to replicate the error and capture the possible jeopardizing response.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Enterprise Linux 8 | tomcat-1:9.0.62-27.el8_9.2 | RHSA-2024:0125 |
| Red Hat Enterprise Linux 9 | tomcat-1:9.0.62-37.el9_3.1 | RHSA-2024:0474 |
| Red Hat Fuse 7.12.1 | tomcat | RHSA-2023:7247 |
| Red Hat JBoss Web Server 5 | tomcat | RHSA-2023:6207 |
| Red Hat JBoss Web Server 5.7 on RHEL 7 | jws5-tomcat-0:9.0.62-18.redhat_00016.1.el7jws | RHSA-2023:6206 |
Frequently Asked Questions
Is CVE-2023-42795 in your dependencies?
O3 Security finds CVE-2023-42795 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.