LWP::UserAgent versions before 6.83 for Perl leak Authorization and Proxy-Authorization headers on cross-origin redirects.
On a 3xx response, the redirect handler strips only Host and Cookie before issuing the follow-up request. Caller-supplied Authorization and Proxy-Authorization headers are sent unchanged to the redirect target, including across scheme, host, or port changes.
A redirect to an attacker controlled host therefore discloses the callers credentials to that host.
Weakness
The product transmits or stores authentication credentials, but it uses an insecure method that is susceptible to unauthorized interception and/or retrieval.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Libwww-perl | Ubuntu | devel | * |
| Libwww-perl | Ubuntu | esm-infra/xenial | * |
| Libwww-perl | Ubuntu | jammy | * |
| Libwww-perl | Ubuntu | noble | * |
| Libwww-perl | Ubuntu | questing | * |
| Libwww-perl | Ubuntu | resolute | * |
| Libwww-perl | Ubuntu | upstream | * |
Potential Mitigations
Related Attack Patterns
- https://cwe.mitre.org/data/definitions/102.html
- https://cwe.mitre.org/data/definitions/474.html
- https://cwe.mitre.org/data/definitions/50.html
- https://cwe.mitre.org/data/definitions/509.html
- https://cwe.mitre.org/data/definitions/551.html
- https://cwe.mitre.org/data/definitions/555.html
- https://cwe.mitre.org/data/definitions/560.html
- https://cwe.mitre.org/data/definitions/561.html
- https://cwe.mitre.org/data/definitions/600.html
- https://cwe.mitre.org/data/definitions/644.html
- https://cwe.mitre.org/data/definitions/645.html
- https://cwe.mitre.org/data/definitions/652.html
- https://cwe.mitre.org/data/definitions/653.html
References
- https://github.com/libwww-perl/libwww-perl/commit/9c4aeb6f2dd32f2b7eaf2d7827cade31ea6cb2c6.patch
- https://github.com/libwww-perl/libwww-perl/pull/284
- https://github.com/libwww-perl/libwww-perl/pull/512
- https://metacpan.org/release/OALDERS/libwww-perl-6.83/changes
- http://www.openwall.com/lists/oss-security/2026/05/12/7