---
id: "CVE-2026-109140"
kind: "vulnerability"
aliases: ["CVE-2026-109140"]
title: "Krill: any logged-in user can forge an admin session token because the encryption nonce resets on restart"
severity: "high"
cvss: 8.4
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: [{"name": "krill", "fixed": ["0.16.1"], "affected": "<= 0.16.0", "ecosystem": "vendor"}]
ecosystems: []
tags: ["auth-required", "infrastructure", "krill", "rpki", "self-hosted"]
not_affected_if: ["not-running-krill"]
published_at: "2026-11-02T16:17:26+00:00"
first_seen_at: "2026-11-02T16:24:04+00:00"
updated_at: "2026-11-02T16:33:09+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-109140", "first_seen_at": "2026-11-02T16:24:04+00:00"}, {"source": "analyst", "url": null, "first_seen_at": "2026-11-02T16:33:09+00:00"}]
---

# Krill: any logged-in user can forge an admin session token because the encryption nonce resets on restart

Krill encrypts each login-session token with a nonce from a counter that resets to 0 on every restart, so the same key and nonce pair is reused. Reused nonces can let an attacker recover session token contents or forge valid tokens.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:krill affected <= 0.16.0 fixed 0.16.1

## How to check

Run `krill --version` (or `krillc --version`). Krill 0.16.0 and earlier is affected; 0.16.1 or later is fixed. Distribution packages may differ, so check the package changelog.

## Fix

Install Krill 0.16.1 or later.

## Timeline

- 2026-11-02T16:24:04+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-109140
- 2026-11-02T16:33:09+00:00 analyst — Read NLnet Labs advisory (.txt) and CNA record: Krill <= 0.16.0 affected, fixed in 0.16.1. Advisory says any user who can log in can forge an admin token (needs a valid login, not anonymous; CVSS AV:N/AC:H/PR:L). No exploitation or PoC seen. Mitigations: none stated by vendor.

## Documents

- [advisory] NLnet Labs advisory CVE-2026-109140 (Krill) https://www.nlnetlabs.nl/downloads/krill/CVE-2026-109140.txt
- [describes] CVE record CVE-2026-109140 (CNA NLnet Labs) https://cveawg.mitre.org/api/cve/CVE-2026-109140

## From the sources

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.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_