#VU26504 Buffer overflow in Screen - CVE-2020-9366

Vulnerability identifier: #VU26504

Vulnerability risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-9366

CWE-ID: CWE-119

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Screen
Other software / Other software solutions

Vendor: GNU

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error when treating the special escape OSC 49. A remote attacker can use a specially crafted output or a special program, trigger memory corruption and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Screen: 3.7.1 - 4.7.0

---

External links
https://www.openwall.com/lists/oss-security/2020/02/25/1
https://lists.gnu.org/archive/html/screen-devel/2020-02/msg00007.html
https://security.gentoo.org/glsa/202003-62
https://www.openwall.com/lists/oss-security/2020/02/06/3

---

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.