CVE-2013-4421

Published Oct 25, 2013 · Updated Nov 3, 2026

Severity · CVSSUNKNOWN · Not scored

Known exploitationNot listed

EPSS / likelihood6.42%

QFinch risk scoreNot available

Original summary

Normalized public record · Updated Nov 3, 2026

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.

Publisher and source text is retained separately from QFinch interpretation.

QFinch assessment

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.

Evidence: public source records

Affected products

Affected scope reported by the available public evidence
Affected package, product or range	Fix status
Consult the referenced vendor advisory for affected versions.	Consult source advisory

Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.

Remediation

Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.

Confirm the affected product and reachable code path exist in your environment.
Apply the vendor-supported patch or mitigation from the primary advisory.
Rescan the exact deployed revision and retain verification evidence.

Review primary references

Evidence coverage

FIRST-EPSSCVE-LIST-V5

SSVC priority: LOW
Confidence: Not available
Aliases: None reported

Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.

Sources and record history

55173 ↗
matt.ucc.asn.au ↗
secure.ucc.asn.au ↗
FEDORA-2013-18593 ↗
openSUSE-SU-2013:1696 ↗
62958 ↗
support.citrix.com ↗
FEDORA-2013-18606 ↗
openSUSE-SU-2013:1616 ↗
[oss-security] 20131010 Re: CVE Request: dropbear sshd daemon 2013.59 release ↗

Record history

Published Oct 25, 2013 · Last refreshed Nov 3, 2026

Original summary QFinch assessment Affected products Remediation Evidence coverage Sources and history

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