Vikunja before 2.7.1 Memory Exhaustion DoS via Trello, Todoist and Microsoft To Do Migrations
Vikunja 2.7.0 and earlier are affected when the Trello or Todoist migration feature is enabled and an admin has registered the OAuth app key. Fixed in 2.7.1.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Exploited
- No known exploitation
- Fix
- Fixed in 2.7.1
- Who is exposed
- Specific setups only
Do first: Check whether your setup matches what the bug needs. Vikunja version 2.7.0 or earlier (before 2.7.1) Trello or Todoist migration feature enabled (migration.trello.enable or migration.todoist.enable) Admin has registered the OAuth app key for the migration feature
- Published
- Last modified
- 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? →
- 15/100 · 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
- 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
Summary
Vikunja before 2.7.1 allocates memory without limits in its Trello, Todoist and Microsoft To Do migration importers, which buffer remote attachment downloads and API responses in memory without size caps. Authenticated users can start a migration that references huge attacker-served attachments or yields oversized API responses, exhausting memory and crashing the shared API process for all tenants.
cve.now Index
- Exploitation?/40Unknown. No CISA SSVC exploitation rating yet
- Exposure8/25Specific setups only, reachable over the network
- Reach?/20Unknown. No tracked technology or package matched
- Severity7.1/10CVSS 7.1
- No patch0/5No signal
What would change the score
- Would score about 65 if added to CISA KEV
- Would score about 60 if CISA's SSVC rates exploitation active
- Would score about 22 if CISA's SSVC rates it automatable
What to do
Check whether your setup matches what the bug needs.
Vikunja version 2.7.0 or earlier (before 2.7.1) Trello or Todoist migration feature enabled (migration.trello.enable or migration.todoist.enable) Admin has registered the OAuth app key for the migration featureUpgrade to a fixed version: 2.7.1.
Timeline
- CVE published
- First seen by cve.now
Affected versions
- go-vikunja vikunja
fixed in 2.7.1
Evidence 2
- Advisory
- Link
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-123525
Is CVE-2026-123525 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
What does this mean?
The bug can exhaust memory during migration, which takes down the shared Vikunja API process for all tenants. This is a denial of service, so the service stops responding until it is restarted.Source: github.com, vulncheck.com
Which versions are affected by CVE-2026-123525?
vikunja: before 2.7.1.Source: cve.now feed data
Am I affected, and how do I check?
Vikunja versions 2.7.0 and earlier, before 2.7.1, are affected. The setup also needs the Trello or Todoist migration feature enabled (migration.trello.enable or migration.todoist.enable) and the admin having registered the OAuth app key for that feature. Check the installed version and these settings to see whether they match.Source: github.com, vulncheck.com
How do I fix CVE-2026-123525?
Upgrade Vikunja to 2.7.1 or later. The facts list no workaround, so the fix is the upgrade.Source: github.com, vulncheck.com