Security readout for executives and security teams
Plain-English summary
Vikunja before 2.0.0 can mishandle backup ZIP files during restore. A malicious archive may write files outside the intended restore directory, and a malformed archive can crash the process after the database has been wiped. This matters most where administrators restore untrusted or poorly controlled backups.
Executive priority
Prioritize remediation for any production or internet-accessible self-hosted Vikunja instance below 2.0.0, especially where multiple administrators handle backups. The issue can affect data integrity and availability, but exploitation appears to require privileged restore access based on available evidence.
Technical view
The restoreConfig function in vikunja/pkg/modules/dump/restore.go trusts ZIP entry names and passes them to file-writing operations without path sanitization. This enables path traversal and arbitrary file overwrite. The restore logic also assumes archive structure and can panic from insufficient slice length, causing immediate process crash after database wipe. Fixed in 2.0.0.
Likely exposure
Self-hosted Vikunja deployments running versions earlier than 2.0.0 are affected. Practical exposure depends on who can invoke the restore workflow and supply ZIP archives. The CVSS vector indicates high privileges are required, but confidentiality, integrity, and availability impacts are high if abused.
Exploitation context
No source in the provided bundle reports active exploitation, and it is not listed as KEV. Abuse requires a crafted ZIP archive reaching the restore process. The most likely scenario is malicious, compromised, or mishandled backup material used by a privileged operator.
Researcher notes
Evidence comes from the CVE record and GitHub advisory. The key weaknesses are CWE-22 path traversal through ZIP metadata and CWE-248 uncaught exception. The advisory identifies version 2.0.0 as fixed. Do not assume broader Vikunja components are affected beyond the CLI restore path described.
Mitigation direction
- Upgrade Vikunja to version 2.0.0 or later.
- Restrict restore access to trusted administrators only.
- Do not restore ZIP archives from untrusted or unverified sources.
- Review vendor advisory and release notes for deployment-specific guidance.
- Back up current data before performing any upgrade or restore operation.
Validation and detection
- Identify all self-hosted Vikunja instances and record their versions.
- Confirm whether any instance runs a version earlier than 2.0.0.
- Review who has permission to perform restore operations.
- Check restore logs for unexpected crashes or failed malformed archive restores.
- Verify upgraded systems report Vikunja 2.0.0 or later.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-22: File access and web shell behavior lookup
File traversal and upload weaknesses can lead teams to review file, web shell, execution, and collection telemetry. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCWE-248: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupDatabase behavior lookup
The CVE wording references database injection or access, so collection and exfiltration review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupFile access behavior lookup
The CVE wording references file access or upload behavior, so file telemetry and web shell review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-27819 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.2 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H1.25.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.2HighVector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/go-vikunja/vikunja/security/advisories/GHSA-42wg-38gx-85rhCVE reference · x_refsource_CONFIRM
- https://vikunja.io/changelog/vikunja-v2.0.0-was-releasedCVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
Uncaught Exception
Uncaught Exception represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.