CVE-2026-86122 json
Rowboat through 0.9.1 Server-Side Request Forgery via Custom MCP Server
published 2mo ago modified last mo. also EUVD-2026-71954
- cvss
- 5.0
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 31%
- public exploits
- 0
- none known
Summary
Rowboat through 0.9.1 fails to validate custom MCP server and webhook URLs, allowing authenticated users to configure arbitrary destinations. Attackers can point these URLs at internal services and cloud metadata endpoints to perform server-side request forgery and enumerate internal network topology.
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- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2mo ago
Exploit prediction
0.37% chance of exploitation in the next 30 days, higher than 31% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N |
| CNA | 3.1 | 5.0 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N |
| CNA | 4.0 | 5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Inferred packages
No advisory lists a package for this vulnerability yet. The CVE names these as products and links their GitHub repository, and the package registry names the same repository, so they are probably the affected packages. Low confidence: the versions are the CVE’s own for the product, and a stack check reports the package as unchecked when there are none.
| ecosystem | package | repository | affected |
|---|---|---|---|
| pypi | rowboat | rowboatlabs/rowboat | no versions given |
Affected products
- rowboatlabs rowboat
Classification
- Weakness
-
- CWE-918 Server-Side Request Forgery
References
-
github.com
/rowboatlabs/rowboat/issues/621
issue-tracking
-
github.com
/rowboatlabs/rowboat/blob/v0.9.1/apps/rowboat/src/application/use-cases/projects/add-custom-mcp-server.use-cas
technical-description
-
github.com
/rowboatlabs/rowboat/blob/v0.9.1/apps/rowboat/src/application/lib/agents-runtime/agent-tools.ts
technical-description
-
github.com
/rowboatlabs/rowboat
product
-
vulncheck.com
/advisories/rowboat-through-0.9.1-server-side-request-forgery-via-custom-mcp-server
third-party-advisory
Sources
- CVE List CVE-2026-86122
- NVD CVE-2026-86122
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.