Multiple vulnerabilities in Lighttpd

Published: 2022-09-29

Risk	Medium
Patch available	YES
Number of vulnerabilities	2
CVE-ID	CVE-2022-41556 CVE-2022-37797
CWE-ID	CWE-401 CWE-476
Exploitation vector	Network
Public exploit	N/A
Vulnerable software Subscribe	lighttpd Server applications / Web servers
Vendor	lighttpd

Security Bulletin

This security bulletin contains information about 2 vulnerabilities.

1) Memory leak

EUVDB-ID: #VU67733

Risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2022-41556

CWE-ID: CWE-401 - Missing release of memory after effective lifetime

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform DoS attack on the target system.

The vulnerability exists due memory leak within the mod_fastcgi and mod_scgi modules when handling a large number of incorrect HTTP requests. A remote attacker can send multiple incorrect HTTP requests to the web server and perform denial of service attack.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

lighttpd: 1.4.0 - 1.4.66

External links

http://www.debian.org/security/2022/dsa-5243

Q & A

Can this vulnerability be exploited remotely?

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

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

2) NULL pointer dereference

EUVDB-ID: #VU67731

Risk: Medium

CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2022-37797

CWE-ID: CWE-476 - NULL Pointer Dereference