#VU106260 Heap-based buffer overflow in zlib - CVE-2023-6992

Vulnerability identifier: #VU106260

Vulnerability risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2023-6992

CWE-ID: CWE-122

Exploitation vector: Network

Exploit availability: No

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

Vendor: Cloudflare

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a boundary error when handling compressed data in deflate.c. A remote attacker can pass specially crafted input to the application, trigger a heap-based buffer overflow and perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

zlib: 0.8 - 1.1.4

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External links
https://github.com/cloudflare/zlib/security/advisories/GHSA-vww9-j87r-4cqh
https://github.com/cloudflare/zlib/commit/8352d108c05db1bdc5ac3bdf834dad641694c13c

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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.