Vikunja has a File Size Limit Bypass via Vikunja Import

published 2026-04-10 6 mo ago modified 2026-10-26 13 d ago also EUVD-2026-21429 , GHSA-qh78-rvg3-cv54 , GO-2026-5582

cvss: 5.4; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 28%
public exploits: 0; none known

Vikunja is an open-source self-hosted task management platform. Prior to 2.3.0, the Vikunja file import endpoint uses the attacker-controlled Size field from the JSON metadata inside the import zip instead of the actual decompressed file content length for the file size enforcement check. By setting Size to 0 in the JSON while including large compressed file entries in the zip, an attacker bypasses the configured maximum file size limit. This vulnerability is fixed in 2.3.0.

Patch / fix

fixed in 2 distros 1 links 2

go code.vikunja.io/api 2.3.0
vikunja vikunja 2.3.0

govulncheck-vulndb openSUSE Leap 16.0 0.0.20260723T184607-160000.1.1

opensuse advisories openSUSE-SU-2026:21483-1

github.com/go-vikunja/vikunja#2575 pull request
github.com/go-vikunja/vikunja/releases/tag/v2.3.0 release

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: partial
Assessed: 6 mo ago (2026-04-14)

Exploit prediction

0.35% chance of exploitation in the next 30 days, higher than 28% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/go-vikunja/vikunja/security/advisories/GHSA-qh78-rvg3-cv54 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.4	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L
GitHub	3.1	5.4	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L
NVD	3.1	7.1	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H

Affected packages

ecosystem	package	affected	fixed in
go	code.vikunja.io/api	<2.3.0 all versions	2.3.0

Affected products

go-vikunja vikunja

Classification

Weakness

CWE-770 Allocation of Resources Without Limits or Throttling

References

github.com /go-vikunja/vikunja/pull/2575
web, issue-tracking
github.com /go-vikunja/vikunja/security/advisories/GHSA-qh78-rvg3-cv54
exploit, web, vendor-advisory, advisory
github.com /go-vikunja/vikunja/releases/tag/v2.3.0
web, release-notes
nvd.nist.gov /vuln/detail/CVE-2026-35602
advisory
github.com /go-vikunja/vikunja
package

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.

Summary