CVE-2026-44722

What it is

pyzipper is a replacement for Python's zipfile that can read and write AES encrypted zip files. Prior to 0.4.0, a Python operator precedence bug in pyzipper/zipfile_aes.py caused the AE-2 format to never be automatically selected during encryption, causing encrypted entries to be written in AE-1 format and exposing the plaintext CRC32 checksum in the ZIP header and, for unseekable zip archives, in the datadescripter section, allowing an attacker who possesses the archive to brute-force candidate plaintexts for small or low-entropy files by comparing CRC32 values. This issue is fixed in version 0.4.0.

At a glance

Exploitability

Can be exploited locally on the machine without logging in. High risk of data exposure.

Exploit odds

0.1% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-07-17 17:17 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-10-24 20:10 UTC Last updatedMost recent change to the record

Details

Published

2026-07-17 17:17 UTC

Last modified

2026-10-24 20:10 UTC

Exploit probability

0.1% · EPSS, next 30 days

Weakness

CWE-480

Record status

Deferred

Attack profile CVSS 3.1 · 6.2

Attack vector

Local

Complexity

Low

Privileges needed

None

User interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

None