SB2019092808 - Heap-based buffer overflow in exim (Alpine package)

Description

This security bulletin contains information about 1 security vulnerability.

1) Heap-based buffer overflow (CVE-ID: CVE-2019-16928)

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

The vulnerability exists due to a boundary error within the string_vformat() function in string.c when processing an overly long argument for EHLO command. A remote non-authenticated attacker can send a very long string as an argument for the EHLO command, trigger a heap-based buffer overflow and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Remediation

Install update from vendor's website.

References

• https://git.alpinelinux.org/aports/commit/?id=d2335b4e04dccdf04c50a64f5d284ca624f43782
• https://git.alpinelinux.org/aports/commit/?id=88668001388ee76944d6ae7493665e620a1f4a57
• https://git.alpinelinux.org/aports/commit/?id=b18f2d1006a7b58b45db8d4af133926aad7826ab
• https://git.alpinelinux.org/aports/commit/?id=f7d89f85688c8091ee157cb2350c0ed40ba8346e