CVE-2026-90898

criticalpriority · track · 11OT risk · elevatedEPSS 0.023 · 83 %ileexploit · PoC
grimoire priorityP1 · Urgent
Exploitable?
Public exploit
1 exploit · PoC
Likely / severe?
2.31% (83rd) EPSS
CVSS 9.8 · critical
Is it mine?
0 products
Check your exposure
Who says so?
— sources

EPSS · scored 2026-10-26

Bifrost registers MCP clients through its management API. A stdio client is a command plus args. Bifrost starts that program in the gateway the moment the client is added. No MCP handshake required. The default is governance.auth_config.is_enabled=false. Auth off means every caller is a local admin. One unauthenticated POST /api/mcp/client is enough to run a program as the Bifrost process user (appuser on the official image).  transports/v2.1.0 refuses an unauthenticated stdio registration with 403. transports/v2.0.0 still allows it.

01

cvss

Technical severity, 0–10. One row per scoring source.

9.8
010

base score 0–10 · higher = more severe · hover a vector to decode

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · reefs@jfrog.comexploitability 3.9 · impact 5.9
v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Hsecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: totalcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-284USCWE-306US
04

exploits (1)

Public proof-of-concept and weaponised exploit code.

05

affected products

Products and version ranges known to be affected.

No affected products recorded.

06

sources

Which sources assert this record, and when.

NVDCVE.orgMITRE
published 2026-09-14modified 2026-09-18
07

references (4) nvd

External citations — patches, advisories, analysis.

scry

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