CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:N/I:N/A:P
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
Percentile
91.3%
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.
Author | Note |
---|---|
mdeslaur | per upstream advisory, “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.” seems introduced by: https://github.com/apache/httpd/commit/a4fba223668c554e06bc78d6e3a88f33d4238ae4 Not sure the Debian patch in 2.4.46-5 is right, need to investigate |
CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:N/I:N/A:P
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
Percentile
91.3%