CVE-2025-43855 json
tRPC 11 WebSocket DoS Vulnerability
published 2025-04-24 18 mo ago modified 2026-06-17 4 mo ago also GHSA-pj3v-9cm8-gvj8 , EUVD-2025-12106
- cvss
- 8.7
- version 4.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 36%
- public exploits
- 0
- none known
Summary
tRPC allows users to build & consume fully typesafe APIs without schemas or code generation. In versions starting from 11.0.0 to before 11.1.1, an unhandled error is thrown when validating invalid connectionParams which crashes a tRPC WebSocket server. This allows any unauthenticated user to crash a tRPC 11 WebSocket server. Any tRPC 11 server with WebSocket enabled with a createContext method set is vulnerable. This issue has been patched in version 11.1.1.
Patch / fix
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 18 mo ago
Exploit prediction
0.42% chance of exploitation in the next 30 days, higher than 36% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| CNA | 4.0 | 8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/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 |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | @trpc/server | >=11.0.0, <11.1.1 |
11.1.1 |
Affected products
- trpc trpc
Classification
References
-
github.com
/trpc/trpc/commit/9beb26c636d44852e0f407f3d7a82ad54df65b4d
web
-
github.com
/trpc/trpc/pull/5839
web
-
github.com
/trpc/trpc/security/advisories/GHSA-pj3v-9cm8-gvj8
web
-
nvd.nist.gov
/vuln/detail/CVE-2025-43855
advisory
-
github.com
/trpc/trpc
package
-
github.com
/trpc/trpc/blob/8cef54eaf95d8abc8484fe1d454b6620eeb57f2f/packages/server/src/adapters/ws.ts#L171
web
Sources
- CVE List CVE-2025-43855
- GitHub Advisory GHSA-pj3v-9cm8-gvj8
- NVD CVE-2025-43855
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