Amazon Linux AMI update for nginx

1) Resource exhaustion

EUVDB-ID: #VU81728

Risk: High

CVSSv3.1: 5.1 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:H/RL:O/RC:C]

CVE-ID: CVE-2023-44487

CWE-ID: CWE-400 - Resource exhaustion

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to improperly control of consumption for internal resources when handling HTTP/2 requests with compressed HEADERS frames. A remote attacker can send a sequence of compressed HEADERS frames followed by RST_STREAM frames and perform a denial of service (DoS) attack, a.k.a. "Rapid Reset".

Note, the vulnerability is being actively exploited in the wild.

Mitigation

Update the affected packages:

i686:
    nginx-mod-stream-1.18.0-1.45.amzn1.i686
    nginx-1.18.0-1.45.amzn1.i686
    nginx-mod-http-geoip-1.18.0-1.45.amzn1.i686
    nginx-mod-http-perl-1.18.0-1.45.amzn1.i686
    nginx-mod-mail-1.18.0-1.45.amzn1.i686
    nginx-mod-http-xslt-filter-1.18.0-1.45.amzn1.i686
    nginx-mod-http-image-filter-1.18.0-1.45.amzn1.i686
    nginx-all-modules-1.18.0-1.45.amzn1.i686
    nginx-debuginfo-1.18.0-1.45.amzn1.i686

src:
    nginx-1.18.0-1.45.amzn1.src

x86_64:
    nginx-all-modules-1.18.0-1.45.amzn1.x86_64
    nginx-1.18.0-1.45.amzn1.x86_64
    nginx-mod-stream-1.18.0-1.45.amzn1.x86_64
    nginx-mod-http-perl-1.18.0-1.45.amzn1.x86_64
    nginx-mod-http-geoip-1.18.0-1.45.amzn1.x86_64
    nginx-mod-mail-1.18.0-1.45.amzn1.x86_64
    nginx-mod-http-xslt-filter-1.18.0-1.45.amzn1.x86_64
    nginx-debuginfo-1.18.0-1.45.amzn1.x86_64
    nginx-mod-http-image-filter-1.18.0-1.45.amzn1.x86_64

Vulnerable software versions

Amazon Linux AMI: All versions

nginx: before 1.18.0-1.45

External links

http://alas.aws.amazon.com/ALAS-2023-1870.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

Yes. This vulnerability is being exploited in the wild.