CVE-2026-102356 (GCVE-0-2026-102356)

Vulnerability from cvelistv5 – Published: 2026-11-06 17:38 – Updated: 2026-11-09 22:44
VLAI
Title
Kroki Mermaid companion SSRF via flowchart image URLs
Summary
Kroki creates diagrams from textual descriptions. From 0.26.0 until 0.31.2, the optional Mermaid companion's mermaid/src/worker.js renders attacker-controlled flowchart image nodes in headless Chromium without a network request policy, even when KROKI_SAFE_MODE is set to secure. An actor who can submit Mermaid source and satisfy any authentication or authorization configured by the deployment can cause the companion to issue HTTP or HTTPS GET requests when requesting PNG output. Exploitation requires the Mermaid companion, PNG rendering through its headless Chromium process, a diagram-submission path available to the actor, and network reachability from the companion to the target. The demonstrated impact is limited to blind request reachability and possible state-changing GET endpoints; response exfiltration, cloud metadata access, port scanning, and access beyond the companion's network reachability are not established. This issue is fixed in version 0.31.2.
Severity
5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-09 22:34 UTC
CWE
  • CWE-918 - Server-Side Request Forgery (SSRF)
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7836 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
yuzutech kroki Affected: >= 0.26.0, < 0.31.2
guessed Create a notification for this product.
Show details on NVD website
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