cbcvebase.
CVE-1999-1053
published 1999-09-13

CVE-1999-1053: guestbook.pl cleanses user-inserted SSI commands by removing text between "" separators, which allows remote attackers to execute arbitrary commands when…

PriorityP345high7.5CVSS 2.0
AVNACLAuNCPIPAP
EXPLOIT
EPSS
85.20%
99.7th percentile
guestbook.pl cleanses user-inserted SSI commands by removing text between "" separators, which allows remote attackers to execute arbitrary commands when guestbook.pl is run on Apache 1.3.9 and possibly other versions, since Apache allows other closing sequences besides "-->".

Affected

2 ranges
VendorProductVersion rangeFixed in
apachehttp_server
matt_wrightmatt_wright_guestbook

Detection & IOCsextracted from sources · hover to see the quote

path/cgi-bin/guestbook.pl
path/guestbook/guestbook.html
filenameguestbook.pl
filenameguestbook.html
  • Monitor HTTP POST requests to /cgi-bin/guestbook.pl with SSI-style payloads in the 'comments' parameter. The exploit injects a payload into the comments field using URI-encoded SSI directives.
  • The vulnerability is exploitable only when HTML posting is enabled in guestbook.pl AND the web server has SSI enabled for the '.html' file type. Detection should look for SSI exec directives written into guestbook.html output files.
  • Apache allows SSI closing sequences other than '-->', meaning sanitization that only strips text between '<!--' and '-->' is bypassable. Look for alternative SSI closing sequences in POST body or written to .html files.
  • After exploitation, a follow-up GET request is made to /guestbook/guestbook.html to trigger the injected SSI command. Correlate a POST to guestbook.pl followed by a GET to guestbook.html from the same source.
  • ·Exploitation requires two non-default conditions to both be true: HTML posting enabled in guestbook.pl, and SSI handler enabled for .html files on the web server. Neither condition alone is sufficient.
  • ·The affected version is guestbook.pl <= 2.3.1. Deployments running newer or patched versions are not affected.
  • ·The vulnerability was confirmed on Apache 1.3.9 but may affect other versions due to Apache's support for non-standard SSI closing sequences.

CVSS provenance

nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P
vendor_redhat9.8CRITICAL
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