CVE-2026-100836

Contrast through 1.20.0 contains a panic vulnerability in the transit-engine endpoint's ciphertextContainer.UnmarshalJSON function that fails to validate decoded ciphertext length before slicing. An authenticated workload with a valid mesh certificate can trigger a runtime panic by submitting a short base64-encoded ciphertext, causing log spam and request failures without crashing the process.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/edgelesssys/contrast/security/advisories/GHSA-3ccm-4qq2-5wrp
https://www.vulncheck.com/advisories/edgeless-systems-contrast-through-1.20.0-denial-of-service-via-ciphertextcontainer
https://github.com/edgelesssys/contrast/security/advisories/GHSA-3ccm-4qq2-5wrp

Configurations

No configuration.

History

28 Sep 2026, 16:17

Type	Values Removed	Values Added
References	~~() https://github.com/edgelesssys/contrast/security/advisories/GHSA-3ccm-4qq2-5wrp -~~	() https://github.com/edgelesssys/contrast/security/advisories/GHSA-3ccm-4qq2-5wrp -

27 Sep 2026, 02:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-27 02:17

Updated : 2026-09-28 16:17

NVD link : CVE-2026-100836

Mitre link : CVE-2026-100836

CVE.ORG link : CVE-2026-100836

JSON object : View

Products Affected

No product.

CWE

CWE-129

Improper Validation of Array Index

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