Medium severity · published Aug 21, 2018
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…
5.3
CVSS
2.7%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.7% · higher than 86% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
8.0 · source: NVD
DS
Dropbear Ssh · Dropbear Ssh Project
through 2018.76 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2018-15599
CVE.org
https://www.cve.org/CVERecord?id=CVE-2018-15599
Mailing List
http://lists.ucc.gu.uwa.edu.au/pipermail/dropbear/2018q3/002108.html
Mailing List
http://lists.ucc.gu.uwa.edu.au/pipermail/dropbear/2018q3/002109.html
Mailing List
https://lists.debian.org/debian-lts-announce/2018/08/msg00026.html
matt.ucc.asn.au
https://matt.ucc.asn.au/dropbear/CHANGES
Third Party Advisory
https://old.reddit.com/r/blackhat/comments/97ywnm/openssh_username_enumeration/e4e05n2/
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