CVE-2026-40968 json
Spring gRPC SecurityContext leaks across requests on authorization failure
published 6mo ago modified 14d ago also GHSA-4g9c-3x4p-mfpp , EUVD-2026-26054
- cvss
- 4.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 6%
- public exploits
- 0
- none known
Summary
When an authenticated user is denied access to a gRPC method, their authenticated identity remains bound to the gRPC worker thread and can be inherited by a subsequent unauthenticated request on the same thread. This may allow the subsequent user to gain escalated permissions.
Affected versions: Spring gRPC: 1.0.0 - 1.0.2 (fixed in 1.0.3). Older, unsupported versions are also affected.
Patch / fix
- maven org.springframework.grpc:spring-grpc 1.0.3
- Spring Spring gRPC 1.0.3
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 6mo ago
Exploit prediction
0.17% chance of exploitation in the next 30 days, higher than 6% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 4.3 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N |
| NVD | 3.1 | 8.8 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| GitHub | 3.1 | 4.2 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| maven | org.springframework.grpc:spring-grpc | <1.0.3 |
1.0.3 |
Affected products
- Spring Spring gRPC
Classification
- Weakness
-
- CWE-653 Improper Isolation or Compartmentalization
References
-
spring.io
/security/cve-2026-40968
web, vendor-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-40968
advisory
-
github.com
/spring-projects/spring-grpc
package
Sources
- CVE List CVE-2026-40968
- GitHub Advisory GHSA-4g9c-3x4p-mfpp
- NVD CVE-2026-40968
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