synced 10 MIN AGO
01 Record

CVE-2026-71424

Onyx: Cross-user OAuth-token leak via /api/mcp/servers* for per-user MCP servers

CriticalPUBLISHEDCNA: GitHub_M
CNA base score9.6 CVSS v3.xCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N
View raw JSON

02 Description

Onyx: Cross-user OAuth-token leak via /api/mcp/servers* for per-user MCP servers

03 Exploitation and scoring

Exploitation
Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.
SSVC decision
  • ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
  • AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
  • Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.
CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.
EPSS probability
0.48% probability of exploitation activity in the next 30 days.
EPSS percentile
Equal to or higher than the score of 41.7% of scored records. A rank, not a probability.
NVD base score
9.6 (CVSS v3.x), scored by the NVD independently of the CNA.
NVD CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N
NVD analysis status
Deferred. NVD last modified this record on 2026-10-22.
Red Hat severity
No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

04 Metadata

Published
2026-08-17 21:28Z2 MO AGO
Last updated
2026-08-18 17:47Z2 MO AGO
Reserved
2026-08-06
Assigning CNA
GitHub_M
Record state
PUBLISHED
Severity
Critical (CVSS 9.6)
CNA CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N
Weaknesses
  • CWE-200Exposure of Sensitive Information to an Unauthorized ActorClass
  • CWE-863Incorrect AuthorizationClass
Data version
5.2
Document digest
8bd2ba04d2234188a6de79aa03a78f9a38e30a77243f915260aaaa2f915537e1

05 Affected products

VendorProductVersionsPlatforms
onyx-dot-apponyx< 3.1.10, >= 3.2.0, < 3.2.14, >= 3.3.0-beta.0, < 4.0.0—

06 References