What’s Vulnerable › Vulnerabilities

CVE-2023-45853

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 3.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2023-10-14 · updated 2026-10-15
• Weakness: CWE-190

Description

MiniZip in zlib through 1.3 has an integer overflow and resultant heap-based buffer overflow in zipOpenNewFileInZip4_64 via a long filename, comment, or extra field. NOTE: MiniZip is not a supported part of the zlib product. NOTE: pyminizip through 0.2.6 is also vulnerable because it bundles an affected zlib version, and exposes the applicable MiniZip code through its compress API.

Affected products

• Smihica Pyminizip: through 0.2.6
• zlib: before 1.3.1 — fixed in 1.3.1

How to fix

Upgrade to a fixed version: zlib 1.3.1. Check the vendor advisory for mitigations.

References

• http://www.openwall.com/lists/oss-security/2023/10/20/9
• http://www.openwall.com/lists/oss-security/2024/01/24/10
• https://chromium.googlesource.com/chromium/src/+/d709fb23806858847131027da95ef4c548813356
• https://chromium.googlesource.com/chromium/src/+/de29dd6c7151d3cd37cb4cf0036800ddfb1d8b61
• https://github.com/madler/zlib/blob/ac8f12c97d1afd9bafa9c710f827d40a407d3266/contrib/README.contrib#L1-L4
• https://github.com/madler/zlib/pull/843
• https://lists.debian.org/debian-lts-announce/2023/11/msg00026.html
• https://pypi.org/project/pyminizip/#history
• https://security.gentoo.org/glsa/202401-18
• https://security.netapp.com/advisory/ntap-20231130-0009/
• https://www.winimage.com/zLibDll/minizip.html
• http://www.openwall.com/lists/oss-security/2023/10/20/9

Get alerted when CVE-2023-45853 or the next vulnerability affects your stack