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.
CVE-2013-4434
- No confirmed exploitation signals yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- —
- EG Score
- 0.0(none)
- EPSS
- 92.2%
- KEV
- Not listed
Published
October 25, 2013
Last Modified
April 29, 2026
References (16)
- secalert@redhathttp://lists.opensuse.org/opensuse-updates/2013-10/msg00061.html
- secalert@redhathttp://lists.opensuse.org/opensuse-updates/2013-11/msg00046.html
- secalert@redhathttp://secunia.com/advisories/55173
- secalert@redhathttp://www.openwall.com/lists/oss-security/2013/10/16/11
- secalert@redhathttp://www.securityfocus.com/bid/62993
- secalert@redhathttps://matt.ucc.asn.au/dropbear/CHANGES
- secalert@redhathttps://secure.ucc.asn.au/hg/dropbear/rev/d7784616409a
- secalert@redhathttps://support.citrix.com/article/CTX216642
- af854a3a-2127-422b-91ae-364da2661108http://lists.opensuse.org/opensuse-updates/2013-10/msg00061.html
- af854a3a-2127-422b-91ae-364da2661108http://lists.opensuse.org/opensuse-updates/2013-11/msg00046.html
- af854a3a-2127-422b-91ae-364da2661108http://secunia.com/advisories/55173
- af854a3a-2127-422b-91ae-364da2661108http://www.openwall.com/lists/oss-security/2013/10/16/11
- af854a3a-2127-422b-91ae-364da2661108http://www.securityfocus.com/bid/62993
- af854a3a-2127-422b-91ae-364da2661108https://matt.ucc.asn.au/dropbear/CHANGES
- af854a3a-2127-422b-91ae-364da2661108https://secure.ucc.asn.au/hg/dropbear/rev/d7784616409a
Data Freshness Timeline
(refreshed 8× in last 7d / 36× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-07-06 02:19 UTCEPSS rescore
- 2026-07-06 02:19 UTCEPSS rescore
- 2026-07-05 05:21 UTCOSV refresh
- 2026-07-05 02:26 UTCEPSS rescore
- 2026-07-04 06:27 UTCEPSS rescore
- 2026-07-01 15:02 UTCEPSS rescore
- 2026-06-30 23:19 UTCEPSS rescore
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- 2026-06-28 04:53 UTCEPSS rescore
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- 2026-06-25 13:46 UTCEPSS rescore
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- 2026-06-23 21:30 UTCEPSS rescore
- 2026-06-22 14:22 UTCEPSS rescore
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- 2026-06-21 14:53 UTCEPSS rescore
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- 2026-06-19 19:23 UTCEPSS rescore
- 2026-06-19 19:22 UTCEPSS rescore
- 2026-06-18 17:49 UTCEPSS rescore
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- 2026-06-17 17:49 UTCEPSS rescore
- 2026-06-16 17:49 UTCEPSS rescore
- 2026-06-16 17:49 UTCEPSS rescore
- 2026-06-16 16:39 UTCOSV refresh
- 2026-06-15 17:44 UTCEPSS rescore
- 2026-06-14 23:14 UTCEPSS rescore
- 2026-06-13 22:57 UTCEPSS rescore
- 2026-06-12 23:08 UTCEPSS rescore
- 2026-06-11 13:56 UTCEPSS rescore
- 2026-06-10 13:18 UTCEPSS rescore
- 2026-06-08 14:14 UTCEPSS rescore
- 2026-06-07 15:22 UTCEPSS rescore
- 2026-06-05 22:44 UTCEPSS rescore
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- 2026-06-05 06:08 UTCEPSS rescore
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- 2026-06-02 20:10 UTCEPSS rescore
- 2026-06-02 20:10 UTCEPSS rescore
- 2026-06-01 13:49 UTCEPSS rescore
- 2026-06-01 13:49 UTCEPSS rescore
- 2026-05-31 22:28 UTCEPSS rescore
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- 2026-05-31 00:14 UTCEPSS rescore
- 2026-05-31 00:14 UTCEPSS rescore
- 2026-05-29 13:41 UTCEPSS rescore
- 2026-05-29 13:41 UTCEPSS rescore
- 2026-05-28 21:50 UTCEG score recompute
- 2026-05-28 21:50 UTCGHSA enrichment
- 2026-05-28 13:42 UTCEPSS rescore
- 2026-05-28 13:42 UTCEPSS rescore
- 2026-05-28 13:42 UTCEPSS rescore
- 2026-05-27 13:38 UTCEPSS rescore
- 2026-05-27 13:38 UTCEPSS rescore
- 2026-05-26 13:41 UTCEPSS rescore
- 2026-05-26 13:41 UTCEPSS rescore
- 2026-05-26 07:16 UTCEPSS rescore
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- 2026-05-24 16:43 UTCEPSS rescore
- 2026-05-22 21:15 UTCEPSS rescore
- 2026-05-22 21:15 UTCEPSS rescore
- 2026-05-22 21:15 UTCEPSS rescore
- 2026-05-22 12:57 UTCOSV refresh
- 2026-05-21 22:39 UTCEPSS rescore
- 2026-05-20 22:37 UTCEPSS rescore
- 2026-05-20 22:37 UTCEPSS rescore
- 2026-05-20 11:21 UTCEPSS rescore
- 2026-05-20 11:21 UTCEPSS rescore
- 2026-05-20 11:21 UTCEPSS rescore
- 2026-05-18 21:29 UTCEPSS rescore
- 2026-05-18 21:29 UTCEPSS rescore
Publicly available exploits
(1 reference)Working exploit code is in the public domain (1 GitHub PoC). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.
- GitHub PoCstyx00/Dropbear_CVE-2013-4434First seen Mar 20, 2016
Dropbear user enumeration (CVE-2013-4434) PoC
Open source ↗
Frequently asked(4)
What is CVE-2013-4434?
When was CVE-2013-4434 disclosed?
Is CVE-2013-4434 actively exploited?
How do I remediate CVE-2013-4434?
Dependency Blast Radius
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