Security readout for executives and security teams
Plain-English summary
Apache Tomcat could allow HTTP request smuggling when it accepts malformed Content-Length headers behind a reverse proxy that also fails to reject them. The risk is conditional, but serious because an attacker can potentially interfere with how requests are interpreted.
Executive priority
Treat as high priority for exposed Tomcat services behind proxies. The issue is configuration-dependent, so teams should quickly identify affected deployments before broader remediation work.
Technical view
CVE-2022-42252 is CWE-444 request smuggling in Apache Tomcat. It affects specified Tomcat 8.5, 9.0, 10.0, and 10.1 ranges when rejectIllegalHeader is false, with 8.5.x noted as defaulting that way, and when a reverse proxy also permits the malformed request.
Likely exposure
Internet-facing Tomcat applications behind reverse proxies are the primary concern, especially Tomcat 8.5.x deployments or any deployment with rejectIllegalHeader set to false.
Exploitation context
The source bundle does not show CISA KEV listing or active exploitation evidence. Exploitation requires a vulnerable Tomcat configuration and a reverse proxy that also fails to reject invalid Content-Length headers.
Researcher notes
Do not assume all Tomcat deployments are exposed. The key conditions are affected version range, rejectIllegalHeader=false, and a permissive reverse proxy. The provided sources do not include weaponization details or confirmed exploitation.
Mitigation direction
- Upgrade Tomcat to a release outside the affected ranges using Apache guidance.
- Ensure rejectIllegalHeader is not set to false.
- Configure reverse proxies to reject malformed Content-Length headers.
- Review Gentoo or distribution advisories if Tomcat came from an OS package.
- Prioritize internet-facing reverse-proxy deployments first.
Validation and detection
- Inventory Tomcat versions across production and staging.
- Check Tomcat configuration for rejectIllegalHeader settings.
- Confirm whether Tomcat is behind any reverse proxy or load balancer.
- Validate proxy behavior for malformed Content-Length rejection without offensive testing.
- Review access logs for unusual request parsing or routing anomalies.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-444: Exact CWE lookup
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Open ATT&CK lookupCVE-2022-42252 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N3.93.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.5HighVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://lists.apache.org/thread/zzcxzvqfdqn515zfs3dxb7n8gty589sqCVE reference
- https://security.gentoo.org/glsa/202305-37CVE reference
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.