CVE-2011-1926
The STARTTLS implementation in Cyrus IMAP Server before 2.4.7 does not properly restrict I/O...
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.
Exploit likelihood
What each source reports
NVD Score used
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.
- Record
CVE-2011-1926- CVSS 2.0
- 5.1 Medium
AV:N/AC:H/Au:N/C:P/I:P/A:P - Weakness
- CWE-264
- Updated
- 2026-11-02
CVE List No score
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.
- Record
CVE-2011-1926- Updated
- 2026-11-02
EUVDEUVD-2011-1924 No score
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.
- Record
EUVD-2011-1924- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-w7v6-vm58-fw22 No score
The STARTTLS implementation in Cyrus IMAP Server before 2.4.7 does not properly restrict I/O...
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.
- Record
GHSA-w7v6-vm58-fw22- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
cyrus-imapd-2.2Debian:5.0 |
before 2.2.13-14+lenny4, plus listed versions 2.2.13-142.2.13-14+lenny12.2.13-14+lenny3 |
2.2.13-14+lenny4 |
cyrus-imapd-2.2Debian:6.0 |
before 2.2.13-19+squeeze1, plus listed versions 2.2.13-19 |
2.2.13-19+squeeze1 |
kolab-cyrus-imapdDebian:6.0 |
before 2.2.13-9.1, plus listed versions 2.2.13-9 |
2.2.13-9.1 |
kolab-cyrus-imapdDebian:5.0 |
before 2.2.13-5+lenny3, plus listed versions 2.2.13-52.2.13-5+lenny2 |
2.2.13-5+lenny3 |
cyrus-imapdRed Hat:enterprise_linux:4::as |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapd-debuginfoRed Hat:enterprise_linux:4::as |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapd-develRed Hat:enterprise_linux:4::as |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapd-murderRed Hat:enterprise_linux:4::as |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapd-nntpRed Hat:enterprise_linux:4::as |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapd-utilsRed Hat:enterprise_linux:4::as |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
Show 31 moreShow less
| Package | Affected | Fixed |
|---|---|---|
perl-CyrusRed Hat:enterprise_linux:4::as |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapdRed Hat:enterprise_linux:4::desktop |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapd-debuginfoRed Hat:enterprise_linux:4::desktop |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapd-develRed Hat:enterprise_linux:4::desktop |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapd-murderRed Hat:enterprise_linux:4::desktop |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapd-nntpRed Hat:enterprise_linux:4::desktop |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapd-utilsRed Hat:enterprise_linux:4::desktop |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
perl-CyrusRed Hat:enterprise_linux:4::desktop |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapdRed Hat:enterprise_linux:4::es |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapd-debuginfoRed Hat:enterprise_linux:4::es |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapd-develRed Hat:enterprise_linux:4::es |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapd-murderRed Hat:enterprise_linux:4::es |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapd-nntpRed Hat:enterprise_linux:4::es |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapd-utilsRed Hat:enterprise_linux:4::es |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
perl-CyrusRed Hat:enterprise_linux:4::es |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapdRed Hat:enterprise_linux:4::ws |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapd-debuginfoRed Hat:enterprise_linux:4::ws |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapd-develRed Hat:enterprise_linux:4::ws |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapd-murderRed Hat:enterprise_linux:4::ws |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapd-nntpRed Hat:enterprise_linux:4::ws |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapd-utilsRed Hat:enterprise_linux:4::ws |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
perl-CyrusRed Hat:enterprise_linux:4::ws |
before 0:2.2.12-15.el4 | 0:2.2.12-15.el4 |
cyrus-imapdRed Hat:enterprise_linux:5::server |
before 0:2.3.7-7.el5_6.4 | 0:2.3.7-7.el5_6.4 |
cyrus-imapd-debuginfoRed Hat:enterprise_linux:5::server |
before 0:2.3.7-7.el5_6.4 | 0:2.3.7-7.el5_6.4 |
cyrus-imapd-develRed Hat:enterprise_linux:5::server |
before 0:2.3.7-7.el5_6.4 | 0:2.3.7-7.el5_6.4 |
cyrus-imapd-perlRed Hat:enterprise_linux:5::server |
before 0:2.3.7-7.el5_6.4 | 0:2.3.7-7.el5_6.4 |
cyrus-imapd-utilsRed Hat:enterprise_linux:5::server |
before 0:2.3.7-7.el5_6.4 | 0:2.3.7-7.el5_6.4 |
cyrus-imapdRed Hat:enterprise_linux:6::server |
before 0:2.3.16-6.el6_1.2 | 0:2.3.16-6.el6_1.2 |
cyrus-imapd-debuginfoRed Hat:enterprise_linux:6::server |
before 0:2.3.16-6.el6_1.2 | 0:2.3.16-6.el6_1.2 |
cyrus-imapd-utilsRed Hat:enterprise_linux:6::server |
before 0:2.3.16-6.el6_1.2 | 0:2.3.16-6.el6_1.2 |
cyrus-imapd-develRed Hat:enterprise_linux:6::server |
before 0:2.3.16-6.el6_1.2 | 0:2.3.16-6.el6_1.2 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2011-1926 is a medium vulnerability (CVSS 5.1) in Cmu Cyrus Imap Server, published May 23, 2011. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 4.00%, the 90th percentile. Fixed in cyrus-imapd-2.2 2.2.13-14+lenny4.
References
redhat.com/support/errata/RHSA-2011-0859.html
lists.fedoraproject.org/pipermail/package-announce/2011-June/061374.html
debian.org/security/2011/dsa-2258
cyrusimap.org/docs/cyrus-imapd/2.4.7/changes.php
mandriva.com/security/advisories?name=MDVSA-2011:100
Show 21 moreShow less
securitytracker.com/id?1025625
bugzilla.cyrusimap.org/show_bug.cgi?id=3423
secunia.com/advisories/44876
openwall.com/lists/oss-security/2011/05/17/2
kb.cert.org/vuls/id/555316
bugzilla.redhat.com/show_bug.cgi?id=705288
exchange.xforce.ibmcloud.com/vulnerabilities/67867
git.cyrusimap.org/cyrus-imapd/patch?id=523a91a5e86c8b9a27a138f04a3e3f2d8786f162
nvd.nist.gov/vuln/detail/CVE-2011-1926
github.com/advisories/GHSA-w7v6-vm58-fw22
access.redhat.com/errata/RHSA-2011:0859
security.access.redhat.com/data/csaf/v2/advisories/2011/rhsa-2011_0859.json
cve.org/CVERecord?id=CVE-2011-1926