#VU57577 Out-of-bounds write in ncurses - CVE-2021-39537

Vulnerability identifier: #VU57577

Vulnerability risk: High

CVSSv4.0: 6.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2021-39537

CWE-ID: CWE-787

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
ncurses
Universal components / Libraries / Libraries used by multiple products

Vendor: Free Software Foundation

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a boundary error when processing untrusted input. A remote attacker can create a specially crafted file, trick the victim into opening it using the affected software, trigger out-of-bounds write and execute arbitrary code on the target system.

Mitigation
Install update from vendor's website.

Vulnerable software versions

ncurses: 6.0 - 6.2

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External links
http://lists.gnu.org/archive/html/bug-ncurses/2020-08/msg00006.html
http://lists.gnu.org/archive/html/bug-ncurses/2021-10/msg00023.html
http://cvsweb.netbsd.org/bsdweb.cgi/pkgsrc/devel/ncurses/patches/patch-ncurses_tinfo_captoinfo.c?rev=1.1&content-type=text/x-cvsweb-markup

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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.