SB2022112546 - Anolis OS update for openssh

Description

This security bulletin contains information about 2 secuirty vulnerabilities.

1) Denial of service (CVE-ID: CVE-2017-15906)

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

The weakness exists in the process_open() function due to improper prevention of write operations in read-only mode. A remote attacker can create zero-length files and cause the service to crash.

Successful exploitation of the vulnerability results in denial of service.

2) User enumeration (CVE-ID: CVE-2018-15473)

The vulnerability allows a remote attacker to enumerate all accounts on the system.

The vulnerability exists due to a logical error in auth2-gss.c, auth2-hostbased.c, and auth2-pubkey.c files when processing authentication requests. A remote attacker can send a specially crafted chain of packets and monitor behavior of openssh server to determine presence of a valid username. The server will drop connection upon receiving a malformed authentication packets if the username is valid.

Remediation

Install update from vendor's website.

References

• https://anas.openanolis.cn/errata/detail/ANSA-2022:0816