SB2018081303 - Multiple vulnerabilities in lighttpd

Description

This security bulletin contains information about 2 vulnerabilities.

1) Path traversal (CVE-ID: N/A)

CWE-ID: CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to insufficient check of path names under certain conditions in mod_alias (mod_alias.c). A remote attacker can submit a specially crafted URL and gain access to potentially sensitive information.

2) Use-after-free (CVE-ID: N/A)

CWE-ID: CWE-416 - Use After Free

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green

The vulnerability allows a remote attacker to gain cause denial of service conditions.

The vulnerability exists due to use-after-free error when processing data passed via Range HTTP header. A remote unauthenticated attacker can send a specially crafted HTTP request to the affected server, trigger use-after-free error and crash the affected web server. 

Remediation

Install update from vendor's website.

References

• https://github.com/lighttpd/lighttpd1.4/commit/2105dae0f9d7a964375ce681e53cb165375f84c1#diff-40a405a...
• https://www.lighttpd.net/2018/8/13/1.4.50/
• https://github.com/lighttpd/lighttpd1.4/commit/d161f53de04bc826ce1bdaeb3dce2c72ca50a3f8