nmap: denial of service condition due to a double free when SSH connection fails
Published Aug 28, 2019
7.5
HIGHCVSS 3.0
EPSS 3.16%
Description
nse_libssh2.cc in Nmap 7.70 is subject to a denial of service condition due to a double free when an SSH connection fails, as demonstrated by a leading \n character to ssh-brute.nse or ssh-auth-methods.nse.
Affected products
No data.
No data.
Red Hat Enterprise Linux 5
nmap
Not affected
Red Hat Enterprise Linux 6
nmap
Not affected
Red Hat Enterprise Linux 7
nmap
Not affected
Red Hat Enterprise Linux 8
nmap
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | nmap | Not affected | n/a |
| Red Hat Enterprise Linux 6 | nmap | Not affected | n/a |
| Red Hat Enterprise Linux 7 | nmap | Not affected | n/a |
| Red Hat Enterprise Linux 8 | nmap | Not affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
Red Hat Enterprise Linux 8 is shipped with a vulnerable version of nmap sources, however, the libssh2 module is explicitly excluded from compilation, and is thus not affected. A future update may fix the source. Red Hat Enterprise Linux 7 and older are shipped with nmap-6.40 and older, which do not contain the libssh2 module.
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:N/I:N/A:H
1 other source (Red Hat) ▾
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
AV:N/AC:L/Au:N/C:N/I:N/A:P
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 2, 2026.
Score over time
2021–2026- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Percentile over time
- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Table of values (12 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 2, 2026 | 3.16% (0.03164) | 87.56th | v5 (v2026.06.15) |
| Jun 15, 2026 | 3.16% (0.03164) | 86.30th | v5 (v2026.06.15) |
| Mar 30, 2025 | 1.17% (0.01169) | 76.72th | v4 (v2025.03.14) |
| Mar 29, 2025 | 2.96% (0.02964) | 77.45th | v4 (v2025.03.14) |
| Mar 17, 2025 | 1.17% (0.01169) | 77.18th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.47% (0.00472) | 76.44th | v3 (v2023.03.01) |
| Feb 8, 2024 | 0.40% (0.00405) | 73.05th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.40% (0.00405) | 69.64th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.18% (0.01183) | 61.76th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.18% (0.01183) | 35.15th | v2 (v2022.01.01) |
| Feb 3, 2022 | 2.31% (0.02314) | 53.75th | v5 (v2026.06.15) |
| Apr 14, 2021 | 2.31% (0.02314) | 0.00th | v1 |
References (12)
- http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00073.html vendor-advisoryx_refsource_SUSE
- http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00075.html vendor-advisoryx_refsource_SUSE
- https://access.redhat.com/security/cve/CVE-2017-18594 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1749181 Issue Tracking
- https://github.com/AMatchandaHaystack/Research/blob/master/Nmap%26libsshDF x_refsource_MISCThird Party Advisory
- https://github.com/nmap/nmap/commit/350bbe0597d37ad67abe5fef8fba984707b4e9ad x_refsource_MISCPatchThird Party Advisory
- https://github.com/nmap/nmap/issues/1077 x_refsource_MISCPatchThird Party Advisory
- https://github.com/nmap/nmap/issues/1227 x_refsource_MISCExploitThird Party Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2017-18594
- https://seclists.org/nmap-announce/2019/0 x_refsource_MISCMailing ListThird Party Advisory
- https://seclists.org/nmap-dev/2018/q2/45 x_refsource_MISCMailing ListThird Party Advisory
- https://www.cve.org/CVERecord?id=CVE-2017-18594
Change history (0)
No recorded changes yet.