CVE-2013-4434

Severity: medium (CVSS 5.0 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 5.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2013-10-25 · updated 2026-06-16
Weakness: CWE-189

Description

Dropbear SSH Server before 2013.59 generates error messages for a failed logon attempt with different time delays depending on whether the user account exists, which allows remote attackers to discover valid usernames.

Affected products

[UNKNOWN] dropbear: before 2013.59 — fixed in 2013.59

How to fix

Upgrade to a fixed version: [UNKNOWN] dropbear 2013.59. Check the vendor advisory for mitigations.

References

http://lists.opensuse.org/opensuse-updates/2013-10/msg00061.html
http://lists.opensuse.org/opensuse-updates/2013-11/msg00046.html
http://secunia.com/advisories/55173
http://www.openwall.com/lists/oss-security/2013/10/16/11
http://www.securityfocus.com/bid/62993
https://matt.ucc.asn.au/dropbear/CHANGES
https://secure.ucc.asn.au/hg/dropbear/rev/d7784616409a
https://support.citrix.com/article/CTX216642
http://lists.opensuse.org/opensuse-updates/2013-10/msg00061.html
http://lists.opensuse.org/opensuse-updates/2013-11/msg00046.html
http://secunia.com/advisories/55173
http://www.openwall.com/lists/oss-security/2013/10/16/11

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