Quick answers
- Is CVE-2026-55759 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-55759 being exploited in the wild.
- How severe is CVE-2026-55759?
- High severity, with a CVSS score of 7.4, published 24 June 2026.
- Which products and versions are affected?
- Rocket.Chat < 8.5.1, < 8.4.4, < 8.3.6, < 8.2.6, < 8.1.6, < 8.0.7, < 7.10.13.
- Is there a fix for CVE-2026-55759?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-55759 attacked?
- It is attacked over the network, in a network appliance.
- Am I affected by CVE-2026-55759?
- Check whether you run Rocket.Chat 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.
Technical details
The Apple Sign-In handler in Rocket.Chat uses the `JWS.verify` function from the `jsrsasign` library, which validates the cryptographic signature but ignores JWT claims. Specifically, the implementation fails to verify the audience (aud), expiration (exp), 'not before' (nbf), or nonce claims. An attacker who obtains a valid Apple identity token—via server logs, intercepted traffic, or a shared developer team environment—can replay that token to authenticate as the target user. Because expiration claims are ignored, the window for replaying these tokens is indefinite. The vulnerability is addressed in versions 8.5.1, 8.4.4, 8.3.6, 8.2.6, 8.1.6, 8.0.7, and 7.10.13.
Affected products
- RocketChat Rocket.Chat < 8.5.1, < 8.4.4, < 8.3.6, < 8.2.6, < 8.1.6, < 8.0.7, < 7.10.13
Timeline
- 2026-06-16: advisory: GitHub security advisory published by Rocket.Chat
- 2026-06-24: disclosed: CVE published to NVD