7.5

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 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.

Data is provided by the National Vulnerability Database (NVD)
Apache ≫ HTTP Server Version1.15.17
Apache ≫ HTTP Server Version2.4.47
Fedoraproject ≫ Fedora Version33
Fedoraproject ≫ Fedora Version34
Debian ≫ Debian Linux Version9.0
Debian ≫ Debian Linux Version10.0
Zu dieser CVE wurde keine CISA KEV oder CERT.AT-Warnung gefunden.
EPSS Metriken
Type Source Score Percentile
EPSS FIRST.org 18.52% 0.95
CVSS Metriken
Source Base Score Exploit Score Impact Score Vector string
nvd@nist.gov 7.5 3.9 3.6
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvd@nist.gov 5 10 2.9
AV:N/AC:L/Au:N/C:N/I:N/A:P
CWE-476 NULL Pointer Dereference

The product dereferences a pointer that it expects to be valid but is NULL.

https://seclists.org/oss-sec/2021/q2/206
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