cbcvebase.
CVE-2002-0840
published 2002-10-11

CVE-2002-0840: Cross-site scripting (XSS) vulnerability in the default error page of Apache 2.0 before 2.0.43, and 1.3.x up to 1.3.26, when UseCanonicalName is "Off" and…

PriorityP432medium6.8CVSS 2.0
AVNACMAuNCPIPAP
EXPLOIT
EPSS
94.01%
99.8th percentile
Cross-site scripting (XSS) vulnerability in the default error page of Apache 2.0 before 2.0.43, and 1.3.x up to 1.3.26, when UseCanonicalName is "Off" and support for wildcard DNS is present, allows remote attackers to execute script as other web page visitors via the Host: header, a different vulnerability than CAN-2002-1157.

Affected

47 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

urlhttp://%3CIMG%20SRC%3D%22%22%20ONERROR%3D%22alert%28document%2Ecookie%29%22%0A%3E.apachesite.org/raise_404
  • XSS payload is injected via the HTTP Host: header, which is reflected unsanitized in Apache's default SSI error page. Monitor/alert on Host header values containing HTML/script tags or URL-encoded equivalents (e.g., %3C, %3E, ONERROR=, <script>).
  • The attack vector requires a crafted Host header containing an injected IMG or script tag (e.g., <IMG SRC="" ONERROR="alert(document.cookie)">) sent to trigger a 404 error page on the vulnerable Apache server.
  • The vulnerability is only exploitable when Apache's UseCanonicalName directive is set to 'Off' and wildcard DNS is present. Check server configuration for this combination.
  • Attacks may result in theft of cookie-based authentication credentials. Monitor for unexpected cookie exfiltration or document.cookie references in error page responses.
  • ·Vulnerability only triggers when UseCanonicalName is 'Off'; servers with UseCanonicalName 'On' are not affected.
  • ·Affected versions are Apache 2.0 before 2.0.43 and Apache 1.3.x up to 1.3.26. Fixed in Apache 2.0.43.
  • ·This is a distinct vulnerability from CAN-2002-1157, though both relate to XSS in Apache error pages.

CVSS provenance

nvdv2.06.8MEDIUMAV:N/AC:M/Au:N/C:P/I:P/A:P
osv6.8MEDIUM
vendor_redhat7.5HIGH
vendor_debian6.8MEDIUM
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