CVE-2026-27819
Published: 25 February 2026
Summary
CVE-2026-27819 is a high-severity Path Traversal (CWE-22) vulnerability in Vikunja Vikunja. Its CVSS base score is 7.2 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 13.3th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-11 (Error Handling).
Deeper analysis
CVE-2026-27819 affects Vikunja, an open-source self-hosted task management platform, in versions prior to 2.0.0. The vulnerability resides in the restoreConfig function within vikunja/pkg/modules/dump/restore.go of the go-vikunja/vikunja repository. It stems from inadequate sanitization of file paths in uploaded ZIP archives used for restoration, enabling path traversal (CWE-22) that allows extraction outside the intended directory. Additionally, malformed archives trigger a runtime panic (CWE-248) after wiping the database, as the code trusts the ZIP's Name attribute directly in os.OpenFile calls without validation and fails to check slice lengths, such as accessing an index of len(ms)-2 on insufficient data at line 154. The issue carries a CVSS v3.1 base score of 7.2 (AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H).
Exploitation requires network access and high privileges (PR:H), typically an authenticated administrator capable of uploading a restoration ZIP archive. Attackers can craft a malicious ZIP to overwrite arbitrary files on the host system, potentially leading to full compromise through confidentiality, integrity, and availability impacts. Alternatively, a minimalist malformed ZIP causes the application to panic immediately after permanently deleting database contents, resulting in data loss and denial of service.
The GitHub security advisory (GHSA-42wg-38gx-85rh) and Vikunja changelog for version 2.0.0 detail the fix, which addresses path sanitization and panic conditions in the restoration logic. Security practitioners should upgrade to Vikunja 2.0.0 or later to mitigate the risks.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-8753
Vulnerability details
Vikunja is an open-source self-hosted task management platform. Prior to version 2.0.0, the restoreConfig function in vikunja/pkg/modules/dump/restore.go of the go-vikunja/vikunja repository fails to sanitize file paths within the provided ZIP archive. A maliciously crafted ZIP can bypass the intended extraction…
more
directory to overwrite arbitrary files on the host system. Additionally, we’ve discovered that a malformed archive triggers a runtime panic, crashing the process immediately after the database has been wiped permanently. The application trusts the metadata in the ZIP archive. It uses the Name attribute of the zip.File struct directly in os.OpenFile calls without validation, allowing files to be written outside the intended directory. The restoration logic assumes a specific directory structure within the ZIP. When provided with a "minimalist" malicious ZIP, the application fails to validate the length of slices derived from the archive contents. Specifically, at line 154, the code attempts to access an index of len(ms)-2 on an insufficiently populated slice, triggering a panic. Version 2.0.0 fixes the issue.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Path traversal in admin restore ZIP enables arbitrary file overwrite (data manipulation/destruction) and malformed input triggers post-wipe panic (DoS via app crash); maps to exploiting the self-hosted app and direct impact primitives.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Directly requires validation of untrusted ZIP metadata (file paths and slice lengths) before any os.OpenFile or database-wipe operations, blocking both path traversal and the panic at restore.go:154.
Mandates graceful error handling for malformed inputs so a crafted archive cannot trigger an unrecoverable runtime panic immediately after permanent database deletion.
Restricts the restoreConfig function to only the minimum set of authorized administrators, reducing the attack surface for an authenticated user who can upload malicious ZIPs.