Home/CVE/Improper Authentication, Missing Authentication for Critical Function, Not Failing Securely ('Failing Open') vulnerabili
CVE

CVE-2026-53913

Improper Authentication, Missing Authentication for Critical Function, Not Failing Securely ('Failing Open') vulnerabili

Improper Authentication, Missing Authentication for Critical Function, Not Failing Securely ('Failing Open') vulnerability in Apache Camel Keycloak Component. The KeycloakSecurityPolicy of camel-keycloak guards a route by running KeycloakSecurityProcessor.beforeProcess(), which performs three checks in sequence: it rejects a request that carries no access token, then - only if requiredRoles is non-empty - validates the roles, and - only if requiredPermissions is non-empty - validates the permissions. The actual cryptographic verification of the bearer access token (signature, issuer and expiry for a local JWT, or active-state and issuer for token introspection) is performed exclusively inside those role and permission checks. KeycloakSecurityPolicy defaults requiredRoles and requiredPermissions to empty - which is the documented 'Basic Setup' - so on a route configured that way the role and permission checks are skipped and the access token is therefore never verified. The token-presence check still rejects a missing token, but an invalid token is accepted: any non-null value in the Authorization: Bearer header - including an arbitrary string or a forged, unsigned JWT - passes the policy and the request reaches the protected route, with no signature, issuer or expiry check and no request to Keycloak. The token is read from the inbound request header because allowTokenFromHeader defaults to true. Because the normal reason to place a route behind this policy is that the route performs server-side work, the bypass results in unauthenticated access to that work.

where the protected route forwards to a code-execution-capable producer, it can result in unauthenticated remote code execution. This defect is independent of CVE-2026-23552: that issue concerned the issuer claim and was fixed by adding a check inside the verification routine, but here the verification routine is not reached at all in the default configuration, so the defect remains. This issue affects Apache Camel: from 4.15.0 before 4.18.3, from 4.19.0 before 4.21.0. Users are recommended to upgrade to version 4.21.0, which fixes the issue. If users are on the 4.18.x releases stream, then they are suggested to upgrade to 4.18.3. For deployments that cannot upgrade immediately, configure a non-empty requiredRoles or requiredPermissions on every KeycloakSecurityPolicy so that the token-verification path is exercised, set allowTokenFromHeader to false where the token is not expected from the request header, or perform token verification at the framework layer ahead of the policy.

EPSS 0.00291
EPSS exploitation odds0.29% · top 79%
Monitor
  • ⚠ NVD has not scored this CVE yet - manual triage required (common for recent CVEs)
Look this up elsewhere - one-click external pivots
How to read a CVE - triage first, then detect and patch
This page is every public fact about CVE-2026-53913, cross-linked. Its job is to answer one question fast - does this need my attention now? - and then hand you the two things you do about it. Here is how an analyst reads it.
Triage: should I act now? Four signals, and they are not interchangeable:
CVSSseverity - how bad it is IF exploited, 0-10. A high CVSS alone is not urgency; a flaw can be a perfect 10 and never actually be attacked. EPSSprobability - a model’s estimate of the chance it is exploited in the next 30 days, 0-1. This is the “will it actually happen” signal. CISA KEVconfirmed - it is being exploited in the wild right now. The strongest signal on the page; KEV beats any score. Weaponisedavailability - public exploits / PoCs, and especially Metasploit modules rated Excellent / Great. Reliable, packaged exploit code means low-skill attackers can use it today.
How they combine: KEV, or a dependable Metasploit module, means patch now regardless of CVSS. High CVSS + low EPSS + no exploit is real but not an emergency - schedule it. Low CVSS but KEV-listed still gets patched now. The verdict above already weighed these for you; this is how it got there.
Then what - two workflows:
Detectwhen you cannot patch today, follow this CVE to the ATT&CK techniques it enables, then Build a SIEM detection (the green button) - author a rule, test it in Atomic, deploy it. That buys visibility while the patch waits. PatchAffected products / packages tell you if you are exposed; Fixed versions by distribution and Vendor advisories give the exact version that closes it.
Reading order for the panels below: verdict + badges, then Public exploits / Metasploit (is it weaponised), then ATT&CK techniques + Sigma / IDS rules (can I detect it), then Affected products / packages + Fixed versions (am I exposed, what patches it), then Threat actors / IOCs (who uses it), then Scoring & timeline / references (the evidence).

Severity & exploitation scoring

EPSS exploitation probability
0.29%
Top 79%odds of exploitation in the next 30 days
CVSS metric silhouette
No structured CVSS vector for this CVE. Older entries often have only a numeric base score - the metric breakdown radar requires a full AV:_/AC:_/... vector string published by NVD.
SSVC triage
No SSVC vulnrichment for this CVE. CISA's Vulnrichment program scores newer CVEs (~2024 onwards) plus selected older critical ones. Use the EPSS probability + KEV status to triage instead.

ATT&CK techniques

8

Techniques this CVE enables. Pills with a solid outline are high confidence - named directly in ATT&CK or Nuclei, or human-curated by CTID; the rest are inferred from the weakness type using MITRE's CVE Mapping Methodology and the CWE → CAPEC chain. Broad, generic-weakness guesses are filtered out. A small marks a technique that N independent sources agree on.

▤ Build a SIEM detection for these techniques
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References & Sources

1
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.