cbcvebase.
CVE-2021-31618
published 2021-06-15

CVE-2021-31618: Apache HTTP Server protocol handler for the HTTP/2 protocol checks received request headers against the size limitations as configured for the server and used…

high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
Apache HTTP Server protocol handler for the HTTP/2 protocol checks received request headers against the size limitations as configured for the server and used for the HTTP/1 protocol as well. On violation of these restrictions and HTTP response is sent to the client with a status code indicating why the request was rejected. This rejection response was not fully initialised in the HTTP/2 protocol handler if the offending header was the very first one received or appeared in a a footer. This led to a NULL pointer dereference on initialised memory, crashing reliably the child process. Since such a triggering HTTP/2 request is easy to craft and submit, this can be exploited to DoS the server. This issue affected mod_http2 1.15.17 and Apache HTTP Server version 2.4.47 only. Apache HTTP Server 2.4.47 was never released.

Affected

15 ranges
VendorProductVersion rangeFixed in
apachehttp_server
apachehttp_server
apachehttpd
apache_software_foundationapache_http_server
debianapache2< apache2 2.4.46-5 (bookworm)apache2 2.4.46-5 (bookworm)
debiandebian_linux
debiandebian_linux
fedoraprojectfedora
fedoraprojectfedora
msrcazl3_mod_http2_2.0.29-3_on_azure_linux_3.0
oracleenterprise_manager_ops_center
oracleinstantis_enterprisetrack
oracleinstantis_enterprisetrack
oracleinstantis_enterprisetrack
oraclezfs_storage_appliance_kit

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
osv7.5HIGH