Unrated

Apache Tomcat FFM Connector invalid CRL configuration failure handling flaw

IdentifiersCVE-2026-53434CWE-390

CVE-2026-53434 is a low-severity vulnerability in Apache Tomcat affecting FFM-based connectors when certificate revocation lists (CRLs) are configured. The issue is described as a Detection of Error Condition Without Action flaw: an invalid CRL configuration is detected, but Tomcat does not trigger the expected failure condition for the affected FFM connector path. The available information indicates the problem is specific to CRL handling in this connector configuration rather than a general Tomcat-wide TLS issue. Affected versions are Apache Tomcat 11.0.0-M1 through 11.0.22, 10.1.0-M7 through 10.1.55, and 9.0.83 through 9.0.118.

For your environment

Are you exposed to this one?

Mallory correlates every CVE against your assets, your vendors, and active adversary campaigns. Know which vulnerabilities matter for you, not just which ones are loud.

Start free trial

ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

The primary impact is incorrect security enforcement and operational behavior when CRLs are configured for an FFM-based connector. Because an invalid CRL configuration does not cause startup or configuration failure as expected, a deployment may continue operating with revocation checking misconfigured or ineffective. This can undermine administrator assumptions about certificate validation posture and may allow connections to be accepted under a weaker-than-intended revocation policy. The provided information does not indicate direct remote code execution, privilege escalation, or memory corruption.

Mitigation

If you can’t patch tonight, do this now.

If immediate upgrade is not possible, avoid relying on the affected FFM-based connector configuration with CRLs until patched, and validate connector/TLS revocation settings through explicit testing rather than assuming invalid CRL configuration will fail closed. Review deployments using CRLs on FFM-based connectors, verify whether revocation checking is functioning as intended, and consider using unaffected connector configurations or temporarily disabling the problematic CRL-dependent setup where operationally feasible. Specific vendor-endorsed mitigations beyond upgrading were not provided in the available content.

Remediation

Patch, then assume compromise.

Upgrade Apache Tomcat to a fixed release: 11.0.23, 10.1.56, or 9.0.119, depending on the deployed branch. These versions are identified by Apache as containing the fix for the invalid CRL configuration handling issue in FFM-based connectors.

PUBLIC EXPLOITS

Exploits

No public exploits tracked yet. Mallory keeps watching.

VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

ACTIVITY FEED

Recent activity

8 sources tracked across advisories and community write-ups. News coverage will land here when it surfaces.

8 SOURCESView more in app

No news coverage yet. Advisories and community discussion only.

What this page doesn’t show

The version that knows your environment.

This page is what’s public. Mallory adds the parts that aren’t: which of your assets are affected, which adversaries are exploiting it right now, which detections to deploy, and what to do tonight.

Start free trial

Exposure mapping

Query your assets running an affected version, and investigate the blast radius.

Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity8

Community discussion across Reddit, Mastodon, and other social sources.

EXTERNAL REFERENCES

MITRE CVE

cve.org · CVE-2026-53434

NVD

nvd.nist.gov/vuln/detail/CVE-2026-53434

MITRE CWE · CWE-390

cwe.mitre.org