SB20231004104 - Ubuntu update for exim4

Description

This security bulletin contains information about 3 vulnerabilities.

1) Out-of-bounds read (CVE-ID: CVE-2023-42114)

CWE-ID: CWE-125 - Out-of-bounds read

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

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

The vulnerability exists due to a boundary condition when handling NTLM challenge requests. A remote attacker can send specially crafted data to the server, trigger an out-of-bounds read error and read contents of memory on the system.

2) Out-of-bounds write (CVE-ID: CVE-2023-42115)

CWE-ID: CWE-787 - Out-of-bounds write

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

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a boundary error when handling AUTH command. A remote non-authenticated attacker can send specially crafted data to the server, trigger an out-of-bounds write and execute arbitrary code on the target system.

3) Stack-based buffer overflow (CVE-ID: CVE-2023-42116)

CWE-ID: CWE-121 - Stack-based buffer overflow

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

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error when handling NTLM challenge requests. A remote unauthenticated attacker can send specially crafted data to the server, trigger a stack-based buffer overflow and execute arbitrary code on the target system.

Remediation

Install update from vendor's website.

References

• https://ubuntu.com/security/notices/USN-6411-1