CVE-2026-63329
Warpgate: x-warpgate-username Header Not Stripped from Client Requests Enables Identity Spoofing to WebSocket Backend Targets
Warpgate is an open source SSH, HTTPS and MySQL bastion host for Linux. Prior to 0.25.6, copy_server_request in warpgate-protocol-http/src/proxy.rs forwards a client-supplied x-warpgate-username header before inject_own_headers appends the authenticated username. Because the request builder preserves repeated values, a proxied backend that trusts the first x-warpgate-username value can authorize an authenticated attacker as another user. The same forwarding policy also accepts the reserved x-warpgate-authentication-type header, and warpgate-common/src/http_headers.rs does not exclude either reserved identity header. This issue is fixed in version 0.25.6.
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
4.9
Warpgate: x-warpgate-username Header Not Stripped from Client Requests Enables Identity Spoofing to WebSocket Backend Targets
Warpgate is an open source SSH, HTTPS and MySQL bastion host for Linux. Prior to 0.25.6, copy_server_request in warpgate-protocol-http/src/proxy.rs forwards a client-supplied x-warpgate-username header before inject_own_headers appends the authenticated username. Because the request builder preserves repeated values, a proxied backend that trusts the first x-warpgate-username value can authorize an authenticated attacker as another user. The same forwarding policy also accepts the reserved x-warpgate-authentication-type header, and warpgate-common/src/http_headers.rs does not exclude either reserved identity header. This issue is fixed in version 0.25.6.
- Record
CVE-2026-63329- CVSS 3.1
- 4.9 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:N - Weakness
- CWE-116, CWE-290
- Updated
- 2026-11-02
EUVDEUVD-2026-84060
4.9
Warpgate is an open source SSH, HTTPS and MySQL bastion host for Linux. Prior to 0.25.6, copy_server_request in warpgate-protocol-http/src/proxy.rs forwards a client-supplied x-warpgate-username header before inject_own_headers appends the authenticated username. Because the request builder preserves repeated values, a proxied backend that trusts the first x-warpgate-username value can authorize an authenticated attacker as another user. The same forwarding policy also accepts the reserved x-warpgate-authentication-type header, and warpgate-common/src/http_headers.rs does not exclude either reserved identity header. This issue is fixed in version 0.25.6.
- Record
EUVD-2026-84060- CVSS 3.1
- 4.9 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:N - Updated
- 2026-11-02
NVD
4.9
Warpgate is an open source SSH, HTTPS and MySQL bastion host for Linux. Prior to 0.25.6, copy_server_request in warpgate-protocol-http/src/proxy.rs forwards a client-supplied x-warpgate-username header before inject_own_headers appends the authenticated username. Because the request builder preserves repeated values, a proxied backend that trusts the first x-warpgate-username value can authorize an authenticated attacker as another user. The same forwarding policy also accepts the reserved x-warpgate-authentication-type header, and warpgate-common/src/http_headers.rs does not exclude either reserved identity header. This issue is fixed in version 0.25.6.
- Record
CVE-2026-63329- CVSS 3.1
- 4.9 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:N - Weakness
- CWE-116, CWE-290
- Updated
- 2026-11-02
OSV
4.9
Warpgate: x-warpgate-username Header Not Stripped from Client Requests Enables Identity Spoofing to WebSocket Backend Targets
Warpgate is an open source SSH, HTTPS and MySQL bastion host for Linux. Prior to 0.25.6, copy_server_request in warpgate-protocol-http/src/proxy.rs forwards a client-supplied x-warpgate-username header before inject_own_headers appends the authenticated username. Because the request builder preserves repeated values, a proxied backend that trusts the first x-warpgate-username value can authorize an authenticated attacker as another user. The same forwarding policy also accepts the reserved x-warpgate-authentication-type header, and warpgate-common/src/http_headers.rs does not exclude either reserved identity header. This issue is fixed in version 0.25.6.
- Record
CVE-2026-63329- CVSS 3.1
- 4.9 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:N - Weakness
- CWE-116, CWE-290
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-63329 is a medium vulnerability (CVSS 4.9) in Warp-tech Warpgate, published September 21, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.31%, the 23rd percentile. No source names a fixed version.
References
github.com/warp-tech/warpgate/security/advisories/GHSA-862h-v6cc-9757
github.com/warp-tech/warpgate/commit/c3748d7585209781b2d3a39ac9941b91d11d9b77
github.com/warp-tech/warpgate/releases/tag/v0.25.6
github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63329.json
nvd.nist.gov/vuln/detail/CVE-2026-63329