Permissions, Privileges, and Access Controls in Cyrus IMAP Server

1) Permissions, Privileges, and Access Controls

EUVDB-ID: #VU45033

Risk: Medium

CVSSv3.1: 4.9 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2011-1926

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to read and manipulate data.

The STARTTLS implementation in Cyrus IMAP Server before 2.4.7 does not properly restrict I/O buffering, which allows man-in-the-middle attackers to insert commands into encrypted sessions by sending a cleartext command that is processed after TLS is in place, related to a "plaintext command injection" attack, a similar issue to CVE-2011-0411.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Cyrus IMAP Server: 2.0.17 - 2.4.5

External links

http://bugzilla.cyrusimap.org/show_bug.cgi?id=3423
http://bugzilla.cyrusimap.org/show_bug.cgi?id=3424
http://git.cyrusimap.org/cyrus-imapd/patch/?id=523a91a5e86c8b9a27a138f04a3e3f2d8786f162
http://lists.fedoraproject.org/pipermail/package-announce/2011-June/061374.html
http://lists.fedoraproject.org/pipermail/package-announce/2011-June/061415.html
http://openwall.com/lists/oss-security/2011/05/17/15
http://openwall.com/lists/oss-security/2011/05/17/2
http://secunia.com/advisories/44670
http://secunia.com/advisories/44876
http://secunia.com/advisories/44913
http://secunia.com/advisories/44928
http://www.cyrusimap.org/docs/cyrus-imapd/2.4.7/changes.php
http://www.debian.org/security/2011/dsa-2242
http://www.debian.org/security/2011/dsa-2258
http://www.kb.cert.org/vuls/id/555316
http://www.mandriva.com/security/advisories?name=MDVSA-2011:100
http://www.redhat.com/support/errata/RHSA-2011-0859.html
http://www.securitytracker.com/id?1025625
http://bugzilla.redhat.com/show_bug.cgi?id=705288
http://exchange.xforce.ibmcloud.com/vulnerabilities/67867

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.