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
Published Aug 21, 2018
5.3
MEDIUMCVSS 3.0
EPSS 2.69%
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.
Affected products
No data.
Configuration 1
- 8.0
Configuration 2
- ≤ 2018.76
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
AV:N/AC:L/Au:N/C:P/I:N/A:N
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 3, 2026.
Score over time
2021–2026- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (19 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 3, 2026 | 2.69% (0.02686) | 85.35th | v5 (v2026.06.15) |
| Jun 15, 2026 | 2.71% (0.02709) | 83.98th | v5 (v2026.06.15) |
| Mar 30, 2025 | 0.53% (0.00534) | 64.73th | v4 (v2025.03.14) |
| Mar 29, 2025 | 2.27% (0.02271) | 74.39th | v4 (v2025.03.14) |
| Mar 17, 2025 | 0.53% (0.00534) | 65.40th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.21% (0.00213) | 60.20th | v3 (v2023.03.01) |
| Mar 16, 2024 | 0.30% (0.00302) | 68.94th | v3 (v2023.03.01) |
| Feb 21, 2024 | 0.33% (0.00331) | 70.36th | v3 (v2023.03.01) |
| Feb 8, 2024 | 0.47% (0.00469) | 74.83th | v3 (v2023.03.01) |
| Aug 14, 2023 | 0.46% (0.00465) | 72.31th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.43% (0.00425) | 70.31th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.02% (0.01018) | 40.69th | v2 (v2022.01.01) |
| Sep 10, 2022 | 1.02% (0.01018) | 38.88th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.02% (0.01018) | 36.86th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.02% (0.01018) | 19.50th | v2 (v2022.01.01) |
| Feb 3, 2022 | 1.25% (0.01247) | 30.57th | v1 |
| Jan 6, 2022 | 1.25% (0.01247) | 29.93th | v1 |
| Sep 1, 2021 | 1.25% (0.01247) | 68.62th | v1 |
| Apr 14, 2021 | 1.25% (0.01247) | 0.00th | v1 |
References (5)
- http://lists.ucc.gu.uwa.edu.au/pipermail/dropbear/2018q3/002108.html x_refsource_MISCMailing ListThird Party Advisory
- http://lists.ucc.gu.uwa.edu.au/pipermail/dropbear/2018q3/002109.html x_refsource_MISCMailing ListThird Party Advisory
- https://lists.debian.org/debian-lts-announce/2018/08/msg00026.html mailing-listx_refsource_MLISTMailing ListThird Party Advisory
- https://matt.ucc.asn.au/dropbear/CHANGES x_refsource_CONFIRM
- https://old.reddit.com/r/blackhat/comments/97ywnm/openssh_username_enumeration/e4e05n2/ x_refsource_MISCThird Party Advisory
| Link | Providers | Tags |
|---|---|---|
| http://lists.ucc.gu.uwa.edu.au/pipermail/dropbear/2018q3/002108.html | x_refsource_MISCMailing ListThird Party Advisory | |
| http://lists.ucc.gu.uwa.edu.au/pipermail/dropbear/2018q3/002109.html | x_refsource_MISCMailing ListThird Party Advisory | |
| https://lists.debian.org/debian-lts-announce/2018/08/msg00026.html | mailing-listx_refsource_MLISTMailing ListThird Party Advisory | |
| https://matt.ucc.asn.au/dropbear/CHANGES | x_refsource_CONFIRM | |
| https://old.reddit.com/r/blackhat/comments/97ywnm/openssh_username_enumeration/e4e05n2/ | x_refsource_MISCThird Party Advisory |
Change history (0)
No recorded changes yet.