CVE-2026-40968
Spring gRPC SecurityContext leaks across requests on authorization failure
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Spring gRPC SecurityContext leaks across requests on authorization failure
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.
- Record
CVE-2026-40968- CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-653
- Updated
- 2026-11-02
EUVDEUVD-2026-26054
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.
- Record
EUVD-2026-26054- CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-4g9c-3x4p-mfpp
Spring gRPC SecurityContext leaks across requests upon authorization failure
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.
- Record
GHSA-4g9c-3x4p-mfpp- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-653
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-40968- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N - CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-653
- Updated
- 2026-11-02
OSV
Spring gRPC SecurityContext leaks across requests on authorization failure
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.
- Record
CVE-2026-40968- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-653
- Updated
- 2026-11-02
OSVGHSA-4g9c-3x4p-mfpp
Spring gRPC SecurityContext leaks across requests upon authorization failure
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.
- Record
GHSA-4g9c-3x4p-mfpp- CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-653
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
org.springframework.grpc:spring-grpcMaven |
before 1.0.3 | 1.0.3 |
org.springframework.grpc:spring-grpcMaven |
before 1.0.3, plus listed versions 0.1.00.10.00.11.00.12.00.2.0 Show 11 moreShow less0.3.00.4.00.5.00.6.00.7.00.8.00.9.01.0.01.0.0-RC11.0.11.0.2 |
1.0.3 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-40968 is a medium vulnerability (CVSS 4.3) in Spring Grpc, published April 28, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.17%, the 6th percentile. Fixed in org.springframework.grpc:spring-grpc 1.0.3.