Vulnerability in Edgelesssys Contrast
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L.
EPSS exploit prediction
EPSS: 0.002 (7.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 7th percentile — 7.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.001 · newest: 0.002 · change: +0.000
Affected products
Weakness classification (CWE)
References
- GitHub Security Advisory (GHSA-3ccm-4qq2-5wrp) (vendor-advisory)
- VulnCheck Advisory: Edgeless Systems Contrast through 1.20.0 Denial of Service via ciphertextContainer (third-party-advisory)
Frequently asked questions
- What is CVE-2026-100836?
- CVE-2026-100836 is a medium-severity vulnerability in Edgelesssys Contrast, classified under Improper Validation of Array Index. CVSS score: 4.3/10. Published 2026-09-27.
- How severe is CVE-2026-100836?
- Medium severity. CVSS v3 base score is 4.3 out of 10.