#VU18027 Out-of-bounds read in libssh2 - CVE-2019-3859

Vulnerability identifier: #VU18027

Vulnerability risk: Medium

CVSSv4.0: 1.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2019-3859

CWE-ID: CWE-125

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
libssh2
Client/Desktop applications / Software for system administration

Vendor: libssh2.org

Description

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to a boundary condition when processing packets in _libssh2_packet_require() and _libssh2_packet_requirev() functions. A remote attacker can trick the victim to connect to a malicious SSH server, trigger out-of-bounds read error and read contents of memory or crash the affected application.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

libssh2: 0.1 - 1.8.0

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External links
https://www.libssh2.org/CVE-2019-3859.html

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.