# MA-1324.052025: MyCERT Advisory - Critical Signature Spoofing Flaw in OpenPGP.js

**Date:** 26 May 2025  
**Source:** https://www.mycert.org.my/portal/advisory?id=MA-1324.052025  
**Advisory ID:** MA-1324.052025

---

**1.0 Introduction**
Recently, GitHub has released security updates to address a critical vulnerability has been identified in OpenPGP.js, an open-source JavScript library widely used to enable end-to-end encryption in web applications.
**2.0 Impact**
This flaw allows attackers to spoof digital signatures on inline-signed and signed+encrypted messages, making tampered content appear as if it were legitimately signed by a trusted sender.
**3.0 Affected Products**
- OpenPGP.js versions 5.0.1 – 5.11.2 and 6.0.0-alpha – 6.1.0, OpenPGP.js v4 is not affected.
**4.0 Recommendations**
CyberSecurity Malaysia encourages users and administrators to review the following GitHub security advisory and apply the necessary updates:
Kindly refer to the following URLs for more information: 
- <https://github.com/openpgpjs/openpgpjs/security/advisories/GHSA-8qff-qr5q-5pr8>
Generally, we advise users of these devices to be updated with the latest security announcements by the vendor and follow best practice security policies to determine which updates should be applied.
For further enquiries, please contact Cyber999 Incident the Response Centre through the following channels:
E-mail: cyber999[at]cybersecurity.my 
Phone: 1-300-88-2999 (monitored during business hours) 
Mobile: +60 19 2665850 (24x7 call incident reporting) 
Business Hours: Mon - Fri 08:30 -17:30 MYT 
Web: [https://www.mycert.org.my](https://www.mycert.org.my/) 
**5.0    References**
- <https://github.com/openpgpjs/openpgpjs/security/advisories/GHSA-8qff-qr5q-5pr8>