cbcvebase.
CVE-2007-6203
published 2007-12-03

CVE-2007-6203: Apache HTTP Server 2.0.x and 2.2.x does not sanitize the HTTP Method specifier header from an HTTP request when it is reflected back in a "413 Request Entity…

PriorityP430medium4.3CVSS 2.0
AVNACMAuNCNIPAN
EXPLOIT
EPSS
80.75%
99.6th percentile
Apache HTTP Server 2.0.x and 2.2.x does not sanitize the HTTP Method specifier header from an HTTP request when it is reflected back in a "413 Request Entity Too Large" error message, which might allow cross-site scripting (XSS) style attacks using web client components that can send arbitrary headers in requests, as demonstrated via an HTTP request containing an invalid Content-length value, a similar issue to CVE-2006-3918.

Affected

26 ranges· showing 25
VendorProductVersion rangeFixed in
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server
apachehttp_server

Detection & IOCsextracted from sources · hover to see the quote

commandecho -en "<script> / HTTP/1.1\nHost: $i\nConnection: close\nContent-length: 0\nContent-length: 0\n\n" | nc -w 4 $i 80
  • Look for HTTP requests where the Method field contains HTML/script tags or XSS payloads (e.g., '<script>') instead of a valid HTTP verb, which will be reflected unsanitized in a 413 error response.
  • Detect exploitation attempts by monitoring for HTTP requests with duplicate or invalid Content-length headers (e.g., two 'Content-length: 0' headers) combined with a non-standard or script-injected HTTP method, triggering a 413 response.
  • Alert on 413 HTTP responses from Apache 2.0.46 through 2.2.4 where the response body echoes back an unsanitized HTTP method string.
  • Monitor Apache access/error logs for requests where the HTTP method field contains characters such as '<', '>', '"', or '/' that are not part of a valid RFC method token, indicating a potential XSS injection attempt.
  • ·The vulnerability is fixed in Apache 2.2.6-3 (Debian) and patched via RHBA-2009:0185 (RHEL 5) / RHBA-2008:0763 (RHEL 4). Unpatched Apache 2.0.x and 2.2.x up to 2.2.4 remain affected. Red Hat does not classify this as a security vulnerability but addressed it as a bug fix.
  • ·Exploitation requires the attacker to force the victim's HTTP client to send an arbitrary malformed HTTP method; standard browsers and plugins do not permit this, significantly limiting real-world exploitability.
  • ·The Apache SVN patch (revision 600645) escapes the request method in built-in HTTP error responses; verify this patch is applied when assessing httpd installations.

CVSS provenance

nvdv2.04.3MEDIUMAV:N/AC:M/Au:N/C:N/I:P/A:N
osv4.3MEDIUM
vendor_debian4.3LOW
vendor_redhat4.3MEDIUM
vendor_ubuntu4.3MEDIUM
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