HTTP header injection vulnerabilities arise when user-supplied data is copied into a response header in an unsafe way. If an attacker can inject newline characters into the header, then they can inject new HTTP headers and also, by injecting an empty line, break out of the headers into the message body and write arbitrary content into the application's response.
Various kinds of attack can be delivered via HTTP header injection vulnerabilities. Any attack that can be delivered via cross-site scripting can usually be delivered via header injection, because the attacker can construct a request which causes arbitrary JavaScript to appear within the response body. Further, it is sometimes possible to leverage header injection vulnerabilities to poison the cache of any proxy server via which users access the application. Here, an attacker sends a crafted request which results in a "split" response containing arbitrary content. If the proxy server can be manipulated to associate the injected response with another URL used within the application, then the attacker can perform a "stored" attack against this URL which will compromise other users who request that URL in future.
Issue remediation
If possible, applications should avoid copying user-controllable data into HTTP response headers. If this is unavoidable, then the data should be strictly validated to prevent header injection attacks. In most situations, it will be appropriate to allow only short alphanumeric strings to be copied into headers, and any other input should be rejected. At a minimum, input containing any characters with ASCII codes less than 0x20 should be rejected.
The value of REST URL parameter 1 is copied into the Location response header. The payload e1a5d%0d%0a4bff4ce4f97 was submitted in the REST URL parameter 1. This caused a response containing an injected HTTP header.
The value of REST URL parameter 2 is copied into the Location response header. The payload 68ea2%0d%0a1bd83478ce3 was submitted in the REST URL parameter 2. This caused a response containing an injected HTTP header.
HTTP/1.1 302 Found Accept-Ranges: bytes Last-Modified: Wed, 17 Nov 2010 15:26:23 GMT Location: http://www.verizonbusiness.com/medium/i/68ea2 1bd83478ce3/chat/invitation/close_off.gif Vary: User-Agent Server: Roxen/4.5.146-release3 Content-Type: text/html Content-Length: 195 Expires: Tue, 17 Nov 2009 09:26:23 GMT Connection: keep-alive Date: Wed, 17 Nov 2010 15:26:23 GMT
See <a href='http://www.verizonbusiness.com/medium/i/68ea2 1bd83478ce3/chat/invitation/close_off.gif'>http://www.verizonbusiness.com/medium/i/68ea2 1bd83478ce3/chat/invitation/close_off.gif</a>
The value of REST URL parameter 3 is copied into the Location response header. The payload 149d9%0d%0a568d57ebe4f was submitted in the REST URL parameter 3. This caused a response containing an injected HTTP header.
The value of REST URL parameter 4 is copied into the Location response header. The payload ade10%0d%0a40775cb91a2 was submitted in the REST URL parameter 4. This caused a response containing an injected HTTP header.
HTTP/1.1 302 Found Accept-Ranges: bytes Last-Modified: Wed, 17 Nov 2010 15:33:13 GMT Location: http://www.verizonbusiness.com/medium/i/liveperson/chat/ade10 40775cb91a2/close_off.gif Vary: User-Agent Server: Roxen/4.5.146-release3 Content-Type: text/html Content-Length: 195 Expires: Tue, 17 Nov 2009 09:33:13 GMT Connection: keep-alive Date: Wed, 17 Nov 2010 15:33:13 GMT
See <a href='http://www.verizonbusiness.com/medium/i/liveperson/chat/ade10 40775cb91a2/close_off.gif'>http://www.verizonbusiness.com/medium/i/liveperson/chat/ade10 40775cb91a2/close_off.gif</a>
The value of REST URL parameter 1 is copied into the Location response header. The payload 30066%0d%0ad4de71cc19b was submitted in the REST URL parameter 1. This caused a response containing an injected HTTP header.
The value of REST URL parameter 2 is copied into the Location response header. The payload b7b64%0d%0ae3f45d0fc84 was submitted in the REST URL parameter 2. This caused a response containing an injected HTTP header.
HTTP/1.1 302 Found Accept-Ranges: bytes Last-Modified: Wed, 17 Nov 2010 15:25:46 GMT Location: http://www.verizonbusiness.com/medium/i/b7b64 e3f45d0fc84/chat/invitation/close_on.gif Vary: User-Agent Server: Roxen/4.5.146-release3 Content-Type: text/html Content-Length: 193 Expires: Tue, 17 Nov 2009 09:25:46 GMT Connection: keep-alive Date: Wed, 17 Nov 2010 15:25:46 GMT
See <a href='http://www.verizonbusiness.com/medium/i/b7b64 e3f45d0fc84/chat/invitation/close_on.gif'>http://www.verizonbusiness.com/medium/i/b7b64 e3f45d0fc84/chat/invitation/close_on.gif</a>
The value of REST URL parameter 3 is copied into the Location response header. The payload f3547%0d%0a7c971715f81 was submitted in the REST URL parameter 3. This caused a response containing an injected HTTP header.
The value of REST URL parameter 4 is copied into the Location response header. The payload 6ae4b%0d%0a46b5ee2c939 was submitted in the REST URL parameter 4. This caused a response containing an injected HTTP header.
HTTP/1.1 302 Found Accept-Ranges: bytes Last-Modified: Wed, 17 Nov 2010 15:32:52 GMT Location: http://www.verizonbusiness.com/medium/i/liveperson/chat/6ae4b 46b5ee2c939/close_on.gif Vary: User-Agent Server: Roxen/4.5.146-release3 Content-Type: text/html Content-Length: 193 Expires: Tue, 17 Nov 2009 09:32:52 GMT Connection: keep-alive Date: Wed, 17 Nov 2010 15:32:52 GMT
See <a href='http://www.verizonbusiness.com/medium/i/liveperson/chat/6ae4b 46b5ee2c939/close_on.gif'>http://www.verizonbusiness.com/medium/i/liveperson/chat/6ae4b 46b5ee2c939/close_on.gif</a>
The value of REST URL parameter 1 is copied into the Location response header. The payload 9b036%0d%0aded05f46b2b was submitted in the REST URL parameter 1. This caused a response containing an injected HTTP header.
The value of REST URL parameter 2 is copied into the Location response header. The payload bcedb%0d%0a8531a820f02 was submitted in the REST URL parameter 2. This caused a response containing an injected HTTP header.
The value of REST URL parameter 3 is copied into the Location response header. The payload 73fd8%0d%0a01ee6be8124 was submitted in the REST URL parameter 3. This caused a response containing an injected HTTP header.
The value of REST URL parameter 4 is copied into the Location response header. The payload 2acc5%0d%0a414e38c44c was submitted in the REST URL parameter 4. This caused a response containing an injected HTTP header.
The value of REST URL parameter 1 is copied into the Location response header. The payload dda45%0d%0a9a2335cc272 was submitted in the REST URL parameter 1. This caused a response containing an injected HTTP header.
The value of REST URL parameter 2 is copied into the Location response header. The payload e68ed%0d%0a97f76305359 was submitted in the REST URL parameter 2. This caused a response containing an injected HTTP header.
The value of REST URL parameter 3 is copied into the Location response header. The payload 9397b%0d%0a5474681341b was submitted in the REST URL parameter 3. This caused a response containing an injected HTTP header.
The value of REST URL parameter 4 is copied into the Location response header. The payload c858b%0d%0a2eb09930c1a was submitted in the REST URL parameter 4. This caused a response containing an injected HTTP header.