# CVE-2026-115906: zip library authentication bypass in AES entry reader

Source: https://junglewise.ai/threats/cve-2026-115906-zip-is-a-zip-library-for-rust-that-supports-reading-and-writing  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-26. Updated: 2026-10-26  
License: CC BY 4.0 with a link back

CVE-2026-115906 · Severity: medium · CVSS 6.5 · Published 2026-10-26

The zip library for Rust, used to read and write compressed archives, fails to verify the authentication tag (HMAC) for encrypted entries in certain conditions. An attacker can modify the contents of encrypted ZIP files without detection, allowing data tampering attacks that bypass cryptographic integrity protection.

Technologies: [zip (crates.io)](https://junglewise.ai/threats/technologies/zip), [Zip-Rs Zip](https://junglewise.ai/threats/technologies/zip-rs-zip). Vendors: [crates.io](https://junglewise.ai/threats/vendors/crates-io), [Zip-Rs](https://junglewise.ai/threats/vendors/zip-rs).

## Quick answers

**Is CVE-2026-115906 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-115906 being exploited in the wild.

**How severe is CVE-2026-115906?** Medium severity, with a CVSS score of 6.5, published 26 October 2026.

**Which products and versions are affected?** zip (crates.io) >= 0.6.0, < 9.0.0, SEMVER:introduced=0.6.0,fixed=9.0.0; Zip-Rs Zip 0.6.0 to 8.x before 9.0.0.

**Is there a fix for CVE-2026-115906?** Yes. zip (crates.io): upgrade to 9.0.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-115906 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-115906?** Check whether you run zip (crates.io) or Zip-Rs Zip at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- zip (crates.io): upgrade to 9.0.0 or later

  ```sh
  cargo update -p zip
  ```


## Technical details

The AES entry reader in src/aes.rs only verifies HMAC when an attacker-controlled data counter reaches zero. If the bounded reader reaches end-of-stream while data_remaining is still positive, or if an encrypted entry has no payload, the reader returns clean end-of-stream without comparing the authentication tag. This affects decryption methods by_index_decrypt, by_name_decrypt, by_path_decrypt, and password-enabled by_index_with_options.

## Affected products

- zip-rs zip 0.6.0 to 8.x before 9.0.0

## Identifiers

- CVE-2026-115906
- GHSA-8hxf-qr8p-62x4

## Timeline

- 2026-10-26: disclosed
- 2026-10-09: patched: Version 9.0.0 released

## References

- [https://github.com/zip-rs/zip2/commit/ec265db0b0602f8ffb9479327397bddefb7e2216](https://github.com/zip-rs/zip2/commit/ec265db0b0602f8ffb9479327397bddefb7e2216)
- [https://github.com/zip-rs/zip2/releases/tag/v9.0.0](https://github.com/zip-rs/zip2/releases/tag/v9.0.0)

## Related threats

- [zip Rust library denial of service in symlink extraction](https://junglewise.ai/threats/cve-2026-115909-zip-is-a-zip-library-for-rust-that-supports-reading-and-writing)
- [zip symlink escape vulnerability in extract](https://junglewise.ai/threats/cve-2026-115908-zip-is-a-zip-library-for-rust-that-supports-reading-and-writing)
- [zip library capacity overflow in legacy decoders](https://junglewise.ai/threats/cve-2026-115907-zip-is-a-zip-library-for-rust-that-supports-reading-and-writing)
- [zip library path traversal via Central Directory mismatch](https://junglewise.ai/threats/cve-2026-115905-zip-is-a-zip-library-for-rust-that-supports-reading-and-writing)
- [RUSTSEC-2026-0369 - ZipStreamReader::extract() and ZipArchive::extract() apply Unix permissions through symlinks…](https://junglewise.ai/threats/rustsec-2026-0369-zipstreamreader-extract-and-ziparchive-extract-apply-427bba66)