Cyber Resilience

CVE-2026-27819

Path Traversal in Vikunja ≤ 2.0.0

Public PoCPath Traversal
Published
25 February 2026
Modified
05 March 2026
Patch / advisory
CVSS Score v3.1 7.2
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0074 51th percentile
Risk Priority 54 floored blend · peak EPSS

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 in the top 49% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

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.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

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 Techniques

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1499 Endpoint Denial of Service Impact
Adversaries may perform Endpoint Denial of Service (DoS) attacks to degrade or block the availability of services to users.
T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-67647Shared CWE-248
CVE-2026-33191Shared CWE-248
CVE-2024-34363Shared CWE-248
CVE-2026-64612Shared CWE-248
CVE-2023-27318Shared CWE-248
CVE-2024-29076Shared CWE-248
CVE-2025-59229Shared CWE-248
CVE-2025-24851Shared CWE-248
CVE-2026-48038Shared CWE-248
CVE-2026-31812Shared CWE-248

Affected Assets

vikunja
vikunja
≤ 2.0.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V5.3.2

Mitigating Controls (NIST 800-53 r5) AI

Enforces the intended directory access authorizations that path traversal would otherwise bypass.

Input validation directly neutralizes special path elements before pathname construction occurs.

Least privilege reduces the impact of any unauthorized file access obtained via traversal.

Security engineering principles include robust exception management to keep the system in a defined state.

Fail-in-known-state reduces the impact when an uncaught exception occurs by preserving a safe condition.

Error handling requirements force structured catching and response to exceptions instead of allowing them to propagate uncaught.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices explicitly require structured exception handling to prevent uncaught exceptions from reaching production.

PR.PS-02 partial match
prevents

Patching/maintenance can remediate known path-traversal flaws in deployed software (partial prevention of exploitability) but does nothing to stop the coding defect from being introduced in the first place.

PR.AA-05 none match
prevents

PR.AA-05 defines and reviews access policies but does not address code-level pathname neutralization, so neither direction prevents CWE-22.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing in development catches path traversal via static/dynamic analysis.

prevents

Secure SDLC mandates input validation and path sanitization that directly prevent path traversal.

prevents

Application security requirements include rules for safe file handling and canonicalization.

prevents

Secure architecture principles require least-privilege file access and directory isolation.

prevents

Secure coding standards explicitly forbid unsafe path construction and mandate safe APIs.

mitigates

Information access restriction limits which files an application may read or write.

References