SB2012103106 - Heap-based buffer overflow in Exim

Description

This security bulletin contains information about 1 security vulnerability.

1) Heap-based buffer overflow (CVE-ID: CVE-2012-5671)

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

The vulnerability exists due to a boundary error in Heap-based buffer overflow in the dkim_exim_query_dns_txt function in dkim.c in Exim 4.70 through 4.80, when DKIM support is enabled and acl_smtp_connect and acl_smtp_rcpt are not set to "warn control = dkim_disable_verify,". A remote attacker can use an email from a malicious DNS server. to trigger 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

• http://lists.fedoraproject.org/pipermail/package-announce/2012-November/091664.html
• http://lists.fedoraproject.org/pipermail/package-announce/2012-October/090900.html
• http://lists.fedoraproject.org/pipermail/package-announce/2012-October/090963.html
• http://lists.opensuse.org/opensuse-security-announce/2012-10/msg00018.html
• http://osvdb.org/86616
• http://secunia.com/advisories/51098
• http://secunia.com/advisories/51115
• http://secunia.com/advisories/51153
• http://secunia.com/advisories/51155
• http://www.debian.org/security/2012/dsa-2566
• http://www.openwall.com/lists/oss-security/2012/10/26/5
• http://www.securityfocus.com/bid/56285
• http://www.ubuntu.com/usn/USN-1618-1
• https://exchange.xforce.ibmcloud.com/vulnerabilities/79615
• https://lists.exim.org/lurker/message/20121026.080330.74b9147b.en.html