Is CVE-2011-1506 being actively exploited?

CVE-2011-1506 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2011-1506?

CVE-2011-1506 has a CVSS 2.0 base score of 6.8 (MEDIUM).

CVE-2011-1506

MEDIUM · CVSS 6.8EPSS 2.5%EU EUVD

The STARTTLS implementation in Kerio Connect 7.1.4 build 2985 and MailServer 6.x does not properly restrict I/O buffering, which allows man-in-the-middle attackers to insert commands into encrypted SMTP 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. NOTE: some of these details are obtained from third party information.

Key facts

CVSS score: 6.8 (v2.0)
Severity: MEDIUM
CVSS vector: AV:N/AC:M/Au:N/C:P/I:P/A:P
Weakness (CWE): CWE-20
EPSS score: 2.5% (85th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2011-1507)
Published: March 22, 2011
NVD last modified: June 16, 2026
Status: Modified

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2011-1507 in the EU Vulnerability Database. Last updated in EUVD on August 6, 2024.

View on the EU Vulnerability Database

Affected products

kerio / connect
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver
kerio / kerio mailserver

and 7 more…

References

http://secunia.com/advisories/43678(Vendor Advisory)
http://www.kb.cert.org/vuls/id/555316(US Government Resource)
http://www.kb.cert.org/vuls/id/MAPG-8D9M4P(US Government Resource)
http://www.securityfocus.com/bid/46767
http://www.vupen.com/english/advisories/2011/0610(Vendor Advisory)
https://exchange.xforce.ibmcloud.com/vulnerabilities/65932

Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

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