CVE-2013-4421

Severity: medium (CVSS 5.0 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 6.4% 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

The buf_decompress function in packet.c in Dropbear SSH Server before 2013.59 allows remote attackers to cause a denial of service (memory consumption) via a compressed packet that has a large size when it is decompressed.

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.fedoraproject.org/pipermail/package-announce/2013-October/119300.html
http://lists.fedoraproject.org/pipermail/package-announce/2013-October/119323.html
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/2013/10/11/4
http://www.securityfocus.com/bid/62958
https://matt.ucc.asn.au/dropbear/CHANGES
https://secure.ucc.asn.au/hg/dropbear/rev/0bf76f54de6f
https://support.citrix.com/article/CTX216642
http://lists.fedoraproject.org/pipermail/package-announce/2013-October/119300.html
http://lists.fedoraproject.org/pipermail/package-announce/2013-October/119323.html

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