cbcvebase.
CVE-2018-1303
published 2018-03-26

CVE-2018-1303: A specially crafted HTTP request header could have crashed the Apache HTTP Server prior to version 2.4.30 due to an out of bound read while preparing data to…

PriorityP277high7.5CVSS 3.0
AVNACLPRNUINSUCNINAH
ITWVulnCheck KEV
Exploited in the wild
EPSS
70.78%
99.3th percentile
A specially crafted HTTP request header could have crashed the Apache HTTP Server prior to version 2.4.30 due to an out of bound read while preparing data to be cached in shared memory. It could be used as a Denial of Service attack against users of mod_cache_socache. The vulnerability is considered as low risk since mod_cache_socache is not widely used, mod_cache_disk is not concerned by this vulnerability.

Affected

9 ranges
VendorProductVersion rangeFixed in
apachehttp_server<= 2.4.29
apache_software_foundationapache_http_server
canonicalubuntu_linux
canonicalubuntu_linux
canonicalubuntu_linux
canonicalubuntu_linux
debianapache2< apache2 2.4.33-1 (bookworm)apache2 2.4.33-1 (bookworm)
debiandebian_linux
debiandebian_linux

Detection & IOCsextracted from sources · hover to see the quote

  • The vulnerability is triggered by a specially crafted HTTP request header targeting Apache servers with mod_cache_socache enabled; monitor for crashes in Apache child processes when mod_cache_socache is active.
  • The vulnerable code path is in mod_cache_socache.c:read_table(); focus detection on out-of-bounds read conditions in this function when processing HTTP headers.
  • The upstream patch is available at SVN revision 1824475; use this to diff and build signatures around the patched code path.
  • ·mod_cache_socache must be explicitly enabled for the server to be exposed to this vulnerability; mod_cache_disk is NOT affected.
  • ·In prefork MPM mode (Red Hat default), only the child process crashes — the main web server process will not be killed, limiting the DoS impact.
  • ·mod_cache_disk is not affected by this vulnerability; only mod_cache_socache is vulnerable.

CVSS provenance

nvdv3.07.5HIGHCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:N/I:N/A:P
osv7.5HIGH
vulncheck7.5HIGH
vendor_debian7.5HIGH
vendor_redhat7.5HIGH
vendor_ubuntu7.5HIGH
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