#VU51834 Use-after-free in SQLite - CVE-2021-20227

Vulnerability identifier: #VU51834

Vulnerability risk: Medium

CVSSv4.0: 4.8 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-20227

CWE-ID: CWE-416

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
SQLite
Server applications / Database software

Vendor: SQLite

Description

The vulnerability allows an attacker to compromise vulnerable system.

The vulnerability exists due to a use-after-free error when processing SELECT queries in "src/select.c" if a subquery with both a correlated WHERE clause and a "HAVING 0" clause is used and the parent query is an aggregate. A remote attacker can execute a specially crafted query to trigger a use-after-free error and execute arbitrary code on the system.

Successful exploitation of the vulnerability may allow an attacker to compromise vulnerable system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

SQLite: 3.0.0 - 3.34.0

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External links
https://bugzilla.redhat.com/show_bug.cgi?id=1924886
https://security.gentoo.org/glsa/202103-04
https://www.sqlite.org/releaselog/3_34_1.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.