SB2018030705 - Multiple vulnerabilities in SourceForge zsh

Description

This security bulletin contains information about 3 secuirty vulnerabilities.

1) Buffer overflow (CVE-ID: CVE-2017-18206)

The vulnerability allows a local attacker to cause DoS condition on the target system.

The weakness exists in the utils.c source code file due to insufficient checks on buffer lengths for symlink expansion. A local attacker can send specially crafted input, trigger memory corruption and cause the service to crash.

2) Improper input validation (CVE-ID: CVE-2018-7549)

The vulnerability allows a local attacker to cause DoS condition on the target system.

The weakness exists in the params.c source code file due to improper handling of hash tables. A local attacker can copy an empty hash table with the typeset -p command and cause the service to crash.

3) NULL pointer dereference (CVE-ID: CVE-2018-7548)

The vulnerability allows a local attacker to cause DoS condition on the target system.

The weakness exists in the subst.c source code file due to a NULL pointer dereference. A local attacker can implement ${(PA)...} characters on an empty array result, trigger a NULL pointer dereference condition and cause the service to crash.

Remediation

Install update from vendor's website.

References

• https://sourceforge.net/p/zsh/code/ci/c7a9cf465dd620ef48d586026944d9bd7a0d5d6d/
• https://sourceforge.net/p/zsh/code/ci/c2cc8b0fbefc9868fa83537f5b6d90fc1ec438dd/
• https://sourceforge.net/p/zsh/code/ci/110b13e1090bc31ac1352b28adc2d02b6d25a102