Quick answers
- Is CVE-2026-109140 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-109140 being exploited in the wild.
- How severe is CVE-2026-109140?
- High severity, with a CVSS score of 8.4, published 2 November 2026.
- Which products and versions are affected?
- NLnet Labs Krill up to and including 0.16.0.
- Is there a fix for CVE-2026-109140?
- Yes: fixed in Krill 0.16.1. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-109140 attacked?
- It is attacked over the network, in a network appliance.
- Am I affected by CVE-2026-109140?
- Check whether you run NLnet Labs Krill 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
- Fixed in: Krill 0.16.1
Technical details
The vulnerability is a cryptographic nonce reuse flaw: Krill encrypts login-session tokens using a counter-based nonce that resets to 0 on every service restart, causing identical (key, nonce) pairs to be reused. This breaks the security of the encryption scheme and allows an attacker with valid login credentials to forge authentication tokens, including administrator tokens, after observing the encryption behavior across restarts.
Affected products
- NLnet Labs Krill up to and including 0.16.0
Timeline
- 2026-11-02: disclosed