CVE-2021-44224CWE-476

Possible NULL dereference or SSRF in forward proxy configurations in Apache HTTP Server 2.4.51 and earlier

published December 20, 2021

Patch now

High probability of exploitation

NVD has not assigned a CVSS score to this record. It sits in the 99.7th percentile for exploit probability.

CVSS
—
EPSS
82%
Percentile
99.7
In the wild
Unconfirmed
What it is

A crafted URI sent to httpd configured as a forward proxy (ProxyRequests on) can cause a crash (NULL pointer dereference) or, for configurations mixing forward and reverse proxy declarations, can allow for requests to be directed to a declared Unix Domain Socket endpoint (Server Side Request Forgery). This issue affects Apache HTTP Server 2.4.7 up to 2.4.51 (included).

The record
Technical detail
CVSS
Not scored
CVSS v4.0
Not supplied
EPSS
0.82295 · 99.7th percentile
Weakness
CWE-476 · NULL Pointer Dereference
Published
2021-12-20T11:20Z
EPSS history
Timeline
  • 20 DEC 11:20Z
    Possible NULL dereference or SSRF in forward proxy configurations in Apache HTTP Server 2.4.51 and earlier
    cvelistv5