Vulnerability Monitor

The vendors, products, and vulnerabilities you care about

CVE-2018-15599

The recv_msg_userauth_request function in svr-auth.c in Dropbear through 2018.76 is prone to a user enumeration vulnerability because username validity affects how fields in SSH_MSG_USERAUTH messages are handled, a similar issue to CVE-2018-15473 in an unrelated codebase.

Security Impact Summary

This vulnerability carries a MEDIUM severity rating with a CVSS v3.1 score of 5.3, indicating it can be exploited remotely over the network with relatively low complexity without requiring user interaction and does not require pre-existing privileges . The vulnerability impacts limited data confidentiality, for affected systems. Impacting 2 products from debian, from dropbear_ssh_project organizations running these solutions should prioritize assessment and patching.

Historical Context

First disclosed in 2018, this vulnerability was reported during a period defined by widespread IoT adoption challenges, mobile security concerns, and the emergence of advanced persistent threat (APT) techniques. Contemporary mitigation strategies focused on secure development practices and third-party component vetting.

Published

2018-08-21T01:29:00.350

Last Modified

2024-11-21T03:51:08.913

Status

Modified

Source

[email protected]

Severity

CVSSv3.0: 5.3 (MEDIUM)

CVSSv2 Vector

AV:N/AC:L/Au:N/C:P/I:N/A:N

Access Vector: NETWORK
Access Complexity: LOW
Authentication: NONE
Confidentiality Impact: PARTIAL
Integrity Impact: NONE
Availability Impact: NONE

Exploitability Score

10.0

Impact Score

2.9

Weaknesses

Type: Primary
CWE-200

Affected Vendors & Products

Type	Vendor	Product	Version/Range	Vulnerable?
Operating System	debian	debian_linux	8.0	Yes
Application	dropbear_ssh_project	dropbear_ssh	≤ 2018.76	Yes

References

http://lists.ucc.gu.uwa.edu.au/pipermail/dropbear/2018q3/002108.html Mailing List, Third Party Advisory ([email protected])
http://lists.ucc.gu.uwa.edu.au/pipermail/dropbear/2018q3/002109.html Mailing List, Third Party Advisory ([email protected])
https://lists.debian.org/debian-lts-announce/2018/08/msg00026.html Mailing List, Third Party Advisory ([email protected])
https://matt.ucc.asn.au/dropbear/CHANGES ([email protected])
https://old.reddit.com/r/blackhat/comments/97ywnm/openssh_username_enumeration/e4e05n2/ Third Party Advisory ([email protected])
http://lists.ucc.gu.uwa.edu.au/pipermail/dropbear/2018q3/002108.html Mailing List, Third Party Advisory (af854a3a-2127-422b-91ae-364da2661108)
http://lists.ucc.gu.uwa.edu.au/pipermail/dropbear/2018q3/002109.html Mailing List, Third Party Advisory (af854a3a-2127-422b-91ae-364da2661108)
https://lists.debian.org/debian-lts-announce/2018/08/msg00026.html Mailing List, Third Party Advisory (af854a3a-2127-422b-91ae-364da2661108)
https://matt.ucc.asn.au/dropbear/CHANGES (af854a3a-2127-422b-91ae-364da2661108)
https://old.reddit.com/r/blackhat/comments/97ywnm/openssh_username_enumeration/e4e05n2/ Third Party Advisory (af854a3a-2127-422b-91ae-364da2661108)

How SecUtils Interprets This CVE

SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For debian's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.