Affected versions of http-signature contain a vulnerability which can allow an attacker in a privileged network position to modify header names and change the meaning of the request, without requiring an updated signature.
This problem occurs because vulnerable versions of http-signature sign the contents of headers, but not the header names.
Proof of Concept
Consider this to be the initial, untampered request:
POST /pay HTTP/1.1
Host: example.com
Date: Thu, 05 Jan 2012 21:31:40 GMT
X-Payment-Source: [email protected]
X-Payment-Destination: [email protected]
Authorization: Signature keyId="Test",algorithm="rsa-sha256",headers="x-payment-source x-payment-destination" MDyO5tSvin5...
And the request is intercepted and tampered as follows:
X-Payment-Source: [email protected] // Emails switched
X-Payment-Destination: [email protected]
Authorization: Signature keyId="Test",algorithm="rsa-sha256",headers="x-payment-destination x-payment-source" MDyO5tSvin5...
In the resulting responses, both requests would pass signature verification without issue.
[email protected]\n
[email protected]\n
Recommendation
Update to version 0.10.0 or higher.
References
Affected versions of
http-signaturecontain a vulnerability which can allow an attacker in a privileged network position to modify header names and change the meaning of the request, without requiring an updated signature.This problem occurs because vulnerable versions of
http-signaturesign the contents of headers, but not the header names.Proof of Concept
Consider this to be the initial, untampered request:
And the request is intercepted and tampered as follows:
In the resulting responses, both requests would pass signature verification without issue.
Recommendation
Update to version 0.10.0 or higher.
References