CVE Catalog

CVE-2026-54770

MediumCVSS 6.1
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.34%

26th percentile - higher than 26% of all known CVEs

Summary

WebOb provides objects for HTTP requests and responses. Prior to 1.8.11, Response._make_location_absolute() in src/webob/response.py checks a Location value for a URI scheme or leading double slash before urllib.parse.urljoin() strips leading C0 control characters and spaces. An attacker-controlled value such as a space followed by a protocol-relative or absolute URL can therefore bypass SCHEME_RE and startswith("//") checks and be normalized to an off-host redirect. Request.relative_url() and webob.exc._HTTPMove subclasses, including HTTPFound, are also affected because they use the same unsafe URL joining behavior or bypass the earlier normalization path. An unauthenticated attacker who can influence an application's redirect target can send users to an attacker-controlled host for phishing or OAuth and SSO token theft, but exploitation requires the user to follow the redirect. This issue is fixed in version 1.8.11.

Risk Assessment

The risk includes redirecting users to malicious sites, potentially leading to phishing, credential theft, or session token theft. The attack requires the application to use WebOb for redirect handling and the attacker to influence the Location value.

Recommendation

It is recommended to immediately upgrade to version 1.8.11 or later. Also, avoid passing unsanitized data to the Location header and apply additional URL validation.

Related vulnerabilities

Original NVD description (English source)

WebOb provides objects for HTTP requests and responses. Prior to 1.8.11, Response._make_location_absolute() in src/webob/response.py checks a Location value for a URI scheme or leading double slash before urllib.parse.urljoin() strips leading C0 control characters and spaces. An attacker-controlled value such as a space followed by a protocol-relative or absolute URL can therefore bypass SCHEME_RE and startswith("//") checks and be normalized to an off-host redirect. Request.relative_url() and webob.exc._HTTPMove subclasses, including HTTPFound, are also affected because they use the same unsafe URL joining behavior or bypass the earlier normalization path. An unauthenticated attacker who can influence an application's redirect target can send users to an attacker-controlled host for phishing or OAuth and SSO token theft, but exploitation requires the user to follow the redirect. This issue is fixed in version 1.8.11.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS