Is CVE-2026-100678 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-100678 being exploited in the wild.

How severe is CVE-2026-100678?

Medium severity, with a CVSS score of 6.5, published 26 September 2026.

Is there a fix for CVE-2026-100678?

A patch was published on 2026-09-11: version 0.15.5 released Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-100678 attacked?

It is attacked over the network, in a web application.

Am I affected by CVE-2026-100678?

Check whether you run Stoatchat 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.

CVE-2026-100678: stoatchat MFA brute force via insufficient rate limiting

CVE-2026-100678 · Severity: medium · CVSS 6.5 · Published 2026-09-26

stoatchat is a chat application that uses multi-factor authentication (MFA) to protect user accounts. The application fails to properly limit repeated login attempts at the account level, allowing attackers who know a password to guess TOTP codes by distributing guesses across multiple IP addresses and reusing MFA challenge tokens. A successful attack bypasses MFA protection and grants full account access.

Technologies: Stoatchat. Vendors: Stoatchat.

Quick answers

Is CVE-2026-100678 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-100678 being exploited in the wild.
How severe is CVE-2026-100678?: Medium severity, with a CVSS score of 6.5, published 26 September 2026.
Which products and versions are affected?: Stoatchat before 0.15.5.
Is there a fix for CVE-2026-100678?: A patch was published on 2026-09-11: version 0.15.5 released Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-100678 attacked?: It is attacked over the network, in a web application.
Am I affected by CVE-2026-100678?: Check whether you run Stoatchat 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 MFA login flow does not enforce account-level attempt limits, relying only on IP-based rate limiting. Attackers can reuse MFA challenge tickets across multiple failed TOTP guesses and distribute attempts across different source IPs to circumvent per-IP rate limiting. The vulnerability affects versions before 0.15.5 and requires knowledge of the target account's password as a precondition.

Affected products

stoatchat stoatchat before 0.15.5

Timeline

2026-09-26: disclosed
2026-09-11: patched: version 0.15.5 released

References

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