SB2019082830 - Out-of-bounds write in dovecot (Alpine package)
Published: August 28, 2019
Security Bulletin ID
SB2019082830
Severity
High
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Code execution
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) 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.
References
- https://git.alpinelinux.org/aports/commit/?id=311f42f1afe58945d1cc08642c2c0bce80fa848f
- https://git.alpinelinux.org/aports/commit/?id=43341d57c42c2ba9f572ee12de44ea680a532416
- https://git.alpinelinux.org/aports/commit/?id=8ff339e0a750d552ff3d3be235aca6f4ddfc6a6f
- https://git.alpinelinux.org/aports/commit/?id=1a3664292d8641c136f1b09d244490108ffe7799
- https://git.alpinelinux.org/aports/commit/?id=b819553afa05bacbf987368d81c9314eba613947