cbcvebase.
CVE-2013-4547
published 2013-11-23

CVE-2013-4547: nginx 0.8.41 through 1.4.3 and 1.5.x before 1.5.7 allows remote attackers to bypass intended restrictions via an unescaped space character in a URI.

PriorityP268high7.5CVSS 2.0
AVNACLAuNCPIPAP
EXPLOIT
EPSS
67.72%
99.2th percentile
nginx 0.8.41 through 1.4.3 and 1.5.x before 1.5.7 allows remote attackers to bypass intended restrictions via an unescaped space character in a URI.

Affected

14 ranges
VendorProductVersion rangeFixed in
debiannginx< nginx 1.4.4-1 (bookworm)nginx 1.4.4-1 (bookworm)
f5nginx>= 0 < 1.4.4-11.4.4-1
f5nginx>= 0 < 1.4.4-11.4.4-1
f5nginx>= 0 < 1.4.4-11.4.4-1
f5nginx>= 0 < 1.4.4-11.4.4-1
f5nginx>= 0.8.41 < 1.4.41.4.4
f5nginx1.5.0 – 1.5.6
opensuseopensuse
opensuseopensuse
opensuseopensuse
opensuseopensuse
suselifecycle_management_server
susestudio_onsite
susewebyast

Detection & IOCsextracted from sources · hover to see the quote

url/file \0.php
  • Detect HTTP requests containing an unescaped space character in the URI — the core indicator of CVE-2013-4547 exploitation attempts against nginx.
  • Use the nginx workaround rule as a detection/blocking signature: flag or block any request whose $request_uri contains a literal space character.
  • The exploit payload pattern is a filename followed by a space and a null byte then a script extension (e.g. '/file \0.php'), used to confuse nginx's URI parser into treating a static file as a PHP script.
  • ·Vulnerability only affects nginx 0.8.41 through 1.4.3 and 1.5.x before 1.5.7; fixed in 1.4.4 and 1.5.7.
  • ·The bypass is rooted in how nginx's HTTP request parser handles URIs with unescaped space characters; configurations using location blocks with script handlers (e.g. PHP-FPM) are most at risk.
  • ·An official patch for older/unsupported versions is available at http://nginx.org/download/patch.2013.space.txt

CVSS provenance

nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P
osv7.5HIGH
vendor_debian7.5HIGH
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