A flaw was found in the libsoup HTTP library that can cause proxy authentication credentials to be sent to unintended destinations. When handling HTTP redirects, libsoup removes the Authorization header but does not remove the Proxy-Authorization header if the request is redirected to a different host. As a result, sensitive proxy credentials may be leaked to third-party servers. Applications using libsoup for HTTP communication may unintentionally expose proxy authentication data.
Weakness
The code transmits data to another actor, but a portion of the data includes sensitive information that should not be accessible to that actor.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Libsoup3 | Ubuntu | esm-apps/jammy | * |
| Libsoup3 | Ubuntu | jammy | * |
| Libsoup3 | Ubuntu | noble | * |
| Libsoup3 | Ubuntu | questing | * |
| Libsoup3 | Ubuntu | upstream | * |
Potential Mitigations
- Compartmentalize the system to have “safe” areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area.
- Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.
Related Attack Patterns
- https://cwe.mitre.org/data/definitions/12.html
- https://cwe.mitre.org/data/definitions/217.html
- https://cwe.mitre.org/data/definitions/612.html
- https://cwe.mitre.org/data/definitions/613.html
- https://cwe.mitre.org/data/definitions/618.html
- https://cwe.mitre.org/data/definitions/619.html
- https://cwe.mitre.org/data/definitions/621.html
- https://cwe.mitre.org/data/definitions/622.html
- https://cwe.mitre.org/data/definitions/623.html