CVE-2023-6992: Cloudflare Zlib

Medium severity, CVSS 5.5. EPSS: 0.2% chance of exploitation in the next 30 days.

Cloudflare version of zlib library was found to be vulnerable to memory corruption issues affecting the deflation algorithm implementation (deflate.c). The issues resulted from improper input validation and heap-based buffer overflow. A local attacker could exploit the problem during compression using a crafted malicious file potentially leading to denial of service of the software. Patches: The issue has been patched in commit 8352d10 https://github.com/cloudflare/zlib/commit/8352d108c05db1bdc5ac3bdf834dad641694c13c . The upstream repository is not affected.

Affected products

• Cloudflare Zlib: before 2023-11-16 (fixed in 2023-11-16)

Published 2024-01-04. Last modified 2026-06-17.