5.3

CVE-2026-100836: Edgeless Systems Contrast through 1.20.0 Denial of Service via ciphertextContainer

Deferred
AliasesGHSA-3ccm-4qq2-5wrpGO-2026-5864
Published 27-09-2026Last modified 28-09-2026

Vulnerability summary

CVE-2026-100836 is a medium (CVSS 5.3) Improper Validation of Array Index vulnerability in edgelesssys contrast. EPSS estimates a 0.15% chance of exploitation in the next 30 days, higher than 3.5% of scored vulnerabilities.

Overall risk
21/100
0100
Low · default modelHow is this calculated?
CVSS score
5.3/10
010
Medium · v4.0 (CVE.org)
EPSS score
0.15%
0%100%
Low · Change unavailable
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Timeline

  1. 27-09-2026
    PublishedVulnerability first disclosed.
  2. 28-09-2026
    Last modifiedVulnerability information updated.

Description

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 metrics

5 scores · 3 sources · 2 versions

EPSS trend

Probability

0.15%

Chance of exploitation in the next 30 days

Percentile

4%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

27-09-202622-10-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Edgelesssys1 product
Github.com/edgelesssys1 product
  • contrast< 1.21.0

2 vendors · 2 products

References

5 links