CVE-2014-3556

Description

The STARTTLS implementation in mail/ngx_mail_smtp_handler.c in the SMTP proxy in nginx 1.5.x and 1.6.x before 1.6.1 and 1.7.x before 1.7.4 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.

Category

6.8
CVSS
Severity: Medium
CVSS 2.0 •
EPSS 48.17% Top 5%
Vendor Advisory marc.info Vendor Advisory nginx.org Vendor Advisory nginx.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
http://marc.info/?l=bugtraq&m=142103967620673&w=2 issue tracking third party advisory vendor advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1126891 issue tracking third party advisory
http://mailman.nginx.org/pipermail/nginx-announce/2014/000144.html mailing list patch vendor advisory
http://nginx.org/download/patch.2014.starttls.txt patch vendor advisory

Frequently Asked Questions

What is the severity of CVE-2014-3556?
CVE-2014-3556 has been scored as a medium severity vulnerability.
How to fix CVE-2014-3556?
To fix CVE-2014-3556, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2014-3556 being actively exploited in the wild?
It is possible that CVE-2014-3556 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~48% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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