#VU18253 Out-of-bounds read in libssh2 - CVE-2019-3862

Vulnerability identifier: #VU18253

Vulnerability risk: Medium

CVSSv4.0: 4 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2019-3862

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 or perform denial of service (DoS) attack.

The vulnerability exists due to a boundary condition when SSH_MSG_CHANNEL_REQUEST packets with an exit status message and no payload are parsed. A remote attacker can trick the victim to connect to a malicious SSH server, trigger out of bounds read and gain access to sensitive information or perform denial of service attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

libssh2: 1.0 - 1.8.0

---

External links
https://www.broadcom.com/support/fibre-channel-networking/security-advisories/brocade-security-advisory-2019-767
https://www.libssh2.org/CVE-2019-3862.html

---

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.