Dropbear 2011.54 through 2018.76 has an inconsistent failure delay that may lead to revealing valid usernames, a different issue than CVE-2…

published 2020-12-30 5 y ago modified 2026-06-17 4 mo ago also EUVD-2019-4528

cvss: 5.3; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.2%; EPSS 1.2% chance of exploitation in 30 days, percentile 69%
public exploits: 0; none known

Dropbear 2011.54 through 2018.76 has an inconsistent failure delay that may lead to revealing valid usernames, a different issue than CVE-2018-15599.

Patch / fix

distros 1

dropbear Debian 14, Debian 13, Debian 12 2019.78-1

debian advisories DEBIAN-CVE-2019-12953

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2019-12953 updated 2025-11-21 cvss 5.3

dropbear: inconsistent failure delay that may lead to revealing valid usernames

Red Hat All currently supported Red Hat products
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

1.24% chance of exploitation in the next 30 days, higher than 69% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
NVD	3.1	5.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:P/I:N/A:N

Classification

Weakness

CWE-203 Observable Discrepancy

References

matt.ucc.asn.au /dropbear/CHANGES
release-notes, third-party-advisory

Sources

CVE List CVE-2019-12953
NVD CVE-2019-12953

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary