# CVE-2026-119186: Forge AES-GCM authentication bypass with invalid tag length

Source: https://junglewise.ai/threats/cve-2026-119186-forge-also-called-node-forge-is-a-native-implementation-of  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-29. Updated: 2026-10-29  
License: CC BY 4.0 with a link back

CVE-2026-119186 · Severity: medium · CVSS 5.9 · Published 2026-10-29

Forge (node-forge) is a JavaScript cryptography library used to implement secure TLS communications in web applications. A flaw in AES-GCM decryption validation allows attackers to bypass authentication checks if an application improperly configures the tag length, potentially accepting forged or tampered encrypted data as legitimate.

Technologies: [node-forge (npm)](https://junglewise.ai/threats/technologies/node-forge). Vendors: [Digital Bazaar](https://junglewise.ai/threats/vendors/digital-bazaar), [npm](https://junglewise.ai/threats/vendors/npm).

## Quick answers

**Is CVE-2026-119186 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-119186 being exploited in the wild.

**How severe is CVE-2026-119186?** Medium severity, with a CVSS score of 5.9, published 29 October 2026.

**Which products and versions are affected?** Digital Bazaar Forge (node-forge) prior to 1.4.1; node-forge (npm) <= 1.4.0, SEMVER:introduced=0,fixed=1.4.1.

**Is there a fix for CVE-2026-119186?** Yes. node-forge (npm): upgrade to 1.4.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-119186 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-119186?** Check whether you run Digital Bazaar Forge (node-forge) or node-forge (npm) 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

- node-forge (npm): upgrade to 1.4.1 or later

  ```sh
  npm install node-forge@1.4.1
  ```


## Technical details

The vulnerability stems from missing validation of the AES-GCM tagLength option in the decipher.start() method. When tagLength is set to zero or a falsy value (null, false, empty string, or '0'), the authentication tag calculation becomes 0 bits, causing both computed and supplied tags to compare as empty and pass validation. Attack requires an application to derive tagLength from untrusted input or use a misconfigured value; default tagLength of 128 bits and fixed valid lengths are unaffected.

## Affected products

- Digital Bazaar Forge (node-forge) prior to 1.4.1

## Identifiers

- CVE-2026-119186
- GHSA-5cwg-6vw7-rj6p

## Timeline

- 2026-10-29: disclosed
- 2026-10-27: patched

## References

- [https://github.com/digitalbazaar/forge/commit/236845d96c71207259f91638d0138bba8e2fd624](https://github.com/digitalbazaar/forge/commit/236845d96c71207259f91638d0138bba8e2fd624)
- [https://github.com/digitalbazaar/forge/releases/tag/v1.4.1](https://github.com/digitalbazaar/forge/releases/tag/v1.4.1)

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