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TI-2026-40262 Aliases CVE-2026-55773GHSA-qmch-v2q9-wg4p

CedarJava has a policy injection vulnerability

Priority MEDIUM 41CWE-94Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-94.

Summary

CedarJava is an open source Java implementation of the Cedar policy language, used for fine-grained authorization decisions. In versions prior to 2.3.6, 3.4.1 and 4.9.0, under certain circumstances, improper input handling could allow Cedar-expression injection via unescaped toCedarExpr(). The toCedarExpr() method on Cedar Value types does not escape special characters (" or \) when converting values to Cedar source code. If an integrator uses toCedarExpr() to build policy text at runtime from user-controlled values, an actor could inject arbitrary Cedar expressions. For example, injecting || true into a permit ... when { ... } clause could make the permit unconditional, or injecting && false into a forbid clause could prevent the forbid from triggering. This issue requires the integrator to use toCedarExpr() to build policy text at runtime from user-controlled input. This vulnerability has been fixed in versions 2.3.6, 3.4.1, and 4.9.0.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00518 44th percentileScored 2026-11-07
Fix Fixed cedar-java (cedar-policy): 2.3.6, 3.4.1, 4.9.0com.cedarpolicy:cedar-java (Maven): 2.3.6, 3.4.1, 4.9.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
cedar-policycedar-javabefore 2.3.6; 3.1.2 to before 3.4.1; 4.0.0 to before 4.9.02.3.6, 3.4.1, 4.9.0Patch availableCNA
—com.cedarpolicy:cedar-java (Maven)before 2.3.62.3.6Patch availableGHSA-qmch-v2q9-wg4p
—com.cedarpolicy:cedar-java (Maven)3.1.2 to before 3.4.13.4.1Patch availableGHSA-qmch-v2q9-wg4p
—com.cedarpolicy:cedar-java (Maven)4.0.0 to before 4.9.04.9.0Patch availableGHSA-qmch-v2q9-wg4p
  • cedar-java Vendorcedar-policy Affected before 2.3.6; 3.1.2 to before 3.4.1; 4.0.0 to before 4.9.0 Fixed in 2.3.6, 3.4.1, 4.9.0 Patch available CNA
  • com.cedarpolicy:cedar-java (Maven) Vendor— Affected before 2.3.6 Fixed in 2.3.6 Patch available GHSA-qmch-v2q9-wg4p
  • com.cedarpolicy:cedar-java (Maven) Vendor— Affected 3.1.2 to before 3.4.1 Fixed in 3.4.1 Patch available GHSA-qmch-v2q9-wg4p
  • com.cedarpolicy:cedar-java (Maven) Vendor— Affected 4.0.0 to before 4.9.0 Fixed in 4.9.0 Patch available GHSA-qmch-v2q9-wg4p

Remediation

  • Fix · CNA cedar-java (cedar-policy) Fixed in 2.3.6, 3.4.1, 4.9.0
  • Fix · GHSA-qmch-v2q9-wg4p com.cedarpolicy:cedar-java (Maven) Fixed in 2.3.6 Advisory →
  • Fix · GHSA-qmch-v2q9-wg4p com.cedarpolicy:cedar-java (Maven) Fixed in 3.4.1 Advisory →
  • Fix · GHSA-qmch-v2q9-wg4p com.cedarpolicy:cedar-java (Maven) Fixed in 4.9.0 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-55773
  2. 2026-10-03 Alias added: GHSA-qmch-v2q9-wg4p

References

  • TI-2026-40261 CedarJava has a type confusion vulnerability CVSS 3.1HIGH 8.8
  • TI-2026-40260 CedarJava has policy injection, type confusion, and incorrect equality comparison vulnerabilities CVSS 3.1HIGH 8.8
  • TI-2026-36628 @cedar-policy/authorization-for-expressjs has an authorization bypass via query string manipulation CVSS 3.1HIGH 8.8

Sources