---
id: CVE-2026-109140
title: >-
  Krill login-session tokens reuse their encryption nonce across restarts, so
  any user who can log in can forge an "admin" token
summary: >-
  The vulnerability is that Krill encrypts every login-session token with a
  nonce built from a counter that is reset to 0 on every Krill restart, so the
  same (key, nonce) pair is used again after each restart.
severity: high
cvss: 8.4
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:L'
cvssSource: cna
cwe:
  - CWE-323
vendor: NLnet Labs
product: Krill
affected:
  - Krill (all versions)
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-11-02T16:12:47.575702Z'
published: '2026-11-02'
updated: '2026-11-02'
sourceUpdated: '2026-11-02T16:12:58.713Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-109140'
references:
  - url: 'https://www.nlnetlabs.nl/downloads/krill/CVE-2026-109140.txt'
tags:
  - cve.org
epss: 0.00309
epssPercentile: 0.23895
ingestedAt: '2026-11-05T19:30:42.705Z'
---

## Overview

The vulnerability is that Krill encrypts every login-session token with a nonce built from a counter that is reset to 0 on every Krill restart, so the same (key, nonce) pair is used again after each restart.

## Affected

- `Krill (all versions)`

## Remediation

This issue is fixed in 0.16.1 and all later versions.