CVE-2017-18594 - Double Free

Severity

50%

Complexity

99%

Confidentiality

48%

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.

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.

CVSS 3.0 Base Score 7.5. CVSS Attack Vector: network. CVSS Attack Complexity: low. CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

CVSS 2.0 Base Score 5. CVSS Attack Vector: network. CVSS Attack Complexity: low. CVSS Vector: (AV:N/AC:L/Au:N/C:N/I:N/A:P).

Demo Examples

Double Free

CWE-415

Double Free

CWE-415

While contrived, this code should be exploitable on Linux distributions which do not ship with heap-chunk check summing turned on.


               
}
free(buf1R2);

Overview

First reported 5 years ago

2019-08-29 00:15:00

Last updated 5 years ago

2019-09-26 12:15:00

Affected Software

Nmap 7.70

7.70

References

openSUSE-SU-2019:2198

openSUSE-SU-2019:2200

https://github.com/AMatchandaHaystack/Research/blob/master/Nmap%26libsshDF

Third Party Advisory

https://github.com/nmap/nmap/commit/350bbe0597d37ad67abe5fef8fba984707b4e9ad

Patch, Third Party Advisory

https://github.com/nmap/nmap/issues/1077

Patch, Third Party Advisory

https://github.com/nmap/nmap/issues/1227

Exploit, Third Party Advisory

https://seclists.org/nmap-announce/2019/0

Mailing List, Third Party Advisory

https://seclists.org/nmap-dev/2018/q2/45

Mailing List, Third Party Advisory

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