Security Digest · Vulnerability record
CVE-2026-27575: Vijkunja has Weak Password Policy Combined with Persistent Sessions After Password Change
Vikunja is an open-source self-hosted task management platform.
CVSS 9.1 Critical EPSS 0.5% · p39
Should you act?
Critical and remotely reachable
No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.
- Not in CISA KEV, but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 0.5%, percentile 39: FIRST’s model estimates a 0.5% chance of exploitation activity in the next 30 days, higher than 39% of all scored CVEs (low). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes
code.vikunja.io/api(Go) <= 0.24.6, no fixed version listed. Check your lockfile, including transitive dependencies.
What it is
Vikunja is an open-source self-hosted task management platform. Prior to version 2.0.0, the application allows users to set weak passwords (e.g., 1234, password) without enforcing minimum strength requirements. Additionally, active sessions remain valid after a user changes their password. An attacker who compromises an account (via brute-force or credential stuffing) can maintain persistent access even after the victim resets their password. Version 2.0.0 contains a fix.
From the GitHub advisory
Summary The application allows users to set weak passwords (e.g., 1234, password) without enforcing minimum strength requirements. Additionally, active sessions remain valid after a user changes their password.
An attacker who compromises an account (via brute-force or credential stuffing) can maintain persistent access even after the victim resets their password.
Details
1. Weak passwords are accepted during registration and password change. 2. No minimum length or strength validation is enforced. 3. After changing the password, previously issued session tokens remain valid. 4. No forced logout occurs across active sessions.
Attack scenario:
Weakness type: CWE-521, CWE-613.
Product: code.vikunja.io/api (Go) · Assigned by: GitHub_M · Published: 2026-02-25
Affected and fixed versions
| Ecosystem | Package | Vulnerable | First fixed |
|---|---|---|---|
| Go | code.vikunja.io/api | <= 0.24.6 | none listed |
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| go-vikunja | vikunja | < 2.0.0 |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_M | 3.1 | 9.1 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
| GitHub | 3.1 | 9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
- Attack vector: network (remotely reachable)
- Attack complexity: low
- Privileges required: none (no login)
- User interaction: none
- Scope: unchanged
CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.
Exploitation and urgency
- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc, automatable yes, technical impact total.
- FIRST EPSS (model of 2026-10-21): 0.46% probability of exploitation activity in the next 30 days; percentile 39.
Timeline
- — CVE record published by GitHub_M
- — GitHub-reviewed advisory GHSA-3ccg-x393-96v8 published (critical)
- — CVE record last updated
Sources and references
Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.
Vulnerability records
- GitHub Advisory GHSA-3ccg-x393-96v8 github.com
- CVE.org record CVE-2026-27575 cve.org
- NVD entry CVE-2026-27575 nvd.nist.gov
Other references from the CVE record and advisory
- github.com github.com
- vikunja.io vikunja.io
- github.com github.com