cbcvebase.
CVE-2021-36160
published 2021-09-16

CVE-2021-36160: A carefully crafted request uri-path can cause mod_proxy_uwsgi to read above the allocated memory and crash (DoS). This issue affects Apache HTTP Server…

PriorityP260high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
62.89%
99.1th percentile
A carefully crafted request uri-path can cause mod_proxy_uwsgi to read above the allocated memory and crash (DoS). This issue affects Apache HTTP Server versions 2.4.30 to 2.4.48 (inclusive).

Affected

22 ranges
VendorProductVersion rangeFixed in
apachehttp_server>= 2.4.30 < 2.4.492.4.49
apachehttpd
apache_software_foundationapache_http_serverApache HTTP Server 2.4 – 2.4.48
debianapache2< apache2 2.4.49-1 (bookworm)apache2 2.4.49-1 (bookworm)
debiandebian_linux
debiandebian_linux
debiandebian_linux
debianuwsgi< apache2 2.4.49-1 (bookworm)apache2 2.4.49-1 (bookworm)
fedoraprojectfedora
fedoraprojectfedora
msrccbl2_httpd_2.4.52-1_on_cbl_mariner_2.0
msrccm1_httpd_2.4.49-1_on_cbl_mariner_1.0
oraclecommunications_cloud_native_core_network_function_cloud_native_environment
oracleenterprise_manager_base_platform
oracleenterprise_manager_base_platform
oraclehttp_server
oraclehttp_server
oracleinstantis_enterprisetrack
oracleinstantis_enterprisetrack
oracleinstantis_enterprisetrack
oraclepeoplesoft_enterprise_peopletools
oraclezfs_storage_appliance_kit

Detection & IOCsextracted from sources · hover to see the quote

  • Target module is mod_proxy_uwsgi; monitor for crafted request uri-paths sent to Apache HTTP Server instances running this module, which trigger an out-of-bounds read and crash (DoS)
  • The vulnerability is exploitable by a remote unauthenticated attacker; no authentication required — monitor for anomalous or malformed URI-path patterns in proxy requests to uwsgi backends
  • Affected version range is Apache HTTP Server 2.4.30 through 2.4.48 inclusive; flag any such versions in asset inventory for priority patching
  • Investigation of CVE-2021-36160 led to discovery of CVE-2021-40438 (SSRF via mod_proxy); if CVE-2021-36160 exploitation is suspected, also audit mod_proxy for request forwarding to attacker-controlled origin servers
  • ·CVE-2021-36160 only affects deployments where mod_proxy_uwsgi is loaded and active; systems not using this module are not vulnerable
  • ·Red Hat Enterprise Linux 9 and Red Hat JBoss Enterprise Application Platform 6 are confirmed not affected; RHEL 6 and 7 packages are out of support scope
  • ·No mitigation is available from Red Hat; the only remediation is upgrading to Apache HTTP Server 2.4.49 or later
  • ·The upstream fix for CVE-2021-36160 introduced a regression in UDS URIs; ensure the regression-fix update (USN-5090-4 or equivalent) is also applied

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/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
vendor_cisco9.0CRITICAL
vendor_apache7.5HIGH
vendor_debian7.5HIGH
vendor_msrc7.5HIGH
vendor_redhat7.5HIGH
vendor_ubuntu7.5HIGH
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