Krill login-session tokens reuse their encryption nonce across restarts, so any user who can log in can forge an "admin" token
Krill up to and including 0.16.0 is affected, once it has been restarted and its nonce counter reset. Fixed in 0.16.1.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Exploited
- No known exploitation
- Fix
- Fixed in 0.16.1
- Who is exposed
- Specific setups only
Do first: Check whether your setup matches what the bug needs. Affected product is Krill up to and including 0.16.0. Krill has been restarted, resetting the nonce counter to 0.
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- Published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 17/100 · provisional
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Specific setups only
- Fix
- Fixed in 0.16.1
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: total
Summary
Krill, the software used to run an RPKI certificate authority, is affected. A user who can already log in can forge a session token that grants administrator privileges.
Read the original description
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.
What to do
Check whether your setup matches what the bug needs.
Affected product is Krill up to and including 0.16.0. Krill has been restarted, resetting the nonce counter to 0.Upgrade to a fixed version: 0.16.1.
Timeline
- CVE published
- First seen by cve.now
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: total
- Record last updated
Affected versions
- NLnet Labs Krill
Version range not reported
Evidence 1
- Advisory
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-109140
What does this mean?
Krill's login-session tokens are encrypted with a nonce, a number meant to be used only once. The nonce counter resets to 0 on every Krill restart, so nonces can be reused, and a user who can log in can forge a token that Krill treats as an admin token.Source: nlnetlabs.nl
Am I affected, and how do I check?
The affected product is Krill up to and including 0.16.0. The problem depends on Krill having been restarted, which resets the nonce counter to 0. To check, compare the installed Krill version against 0.16.0 and note whether the instance has restarted since.Source: nlnetlabs.nl
What should I do about it?
Install Krill 0.16.1 or later, which is the fixed version.Source: nlnetlabs.nl
Is it being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data