SB2019100719 - OpenSUSE Linux update for dovecot23
Published: October 7, 2019
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 3 secuirty vulnerabilities.
1) NULL pointer dereference (CVE-ID: CVE-2019-11494)
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a NULL pointer dereference error within Submission-login when processing authentication. A remote attacker can unexpectedly abort the authentication process by disconnecting from the server during authentication and cause the software to crash.
2) Resource management error (CVE-ID: CVE-2019-11499)
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to incorrect resource management error within the submission-login when processing incorrect authentication messages over TLS secure channel. A remote attacker can send an invalid authentication message and crash the service.
3) Out-of-bounds write (CVE-ID: CVE-2019-11500)
The vulnerability allows a remote attacker to compromise vulnerable system.
The vulnerability exists due to a boundary error within IMAP and ManageSieve protocol implementation the when scanning data in quoted strings. A remote attacker can send a specially crafted request to the affected server, trigger out-of-bounds write and execute arbitrary code on the target system.
Exploitation example:
perl -e 'print "a id (\"foo\" \"".("x"x1021)."\\A\" \"bar\"
\"\000".("x"x1020)."\\A\")\n"' | nc localhost 143
Remediation
Install update from vendor's website.