Vikunja before 2.7.1 Memory Exhaustion via Unbounded Avatar Size Cache

published 2026-10-22 21d ago modified 2026-11-08 4d ago also EUVD-2026-119408 , GHSA-3x3m-2j93-w46j

Unreviewed: the maintainers' own advisory

Published by the maintainers on their GitHub repository go-vikunja/vikunja. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.

cvss: 6.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 23%
public exploits: 0; none known

Vikunja before 2.7.1 contains an uncontrolled resource consumption vulnerability that allows authenticated users to exhaust server memory by requesting avatars at many distinct sizes. Attackers can upload a noisy avatar and fetch it at each size up to 1024, caching roughly a gigabyte per account without eviction and causing the API process to be OOM-killed.

Patch / fix

fixed in 1

go-vikunja vikunja 2.7.1

Is CVE-2026-123523 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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Exploit prediction

0.31% chance of exploitation in the next 30 days, higher than 23% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by	version	score	vector
CNA	4.0	7.1	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CNA	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CNA	4.0	7.1	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
NVD	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected products

go-vikunja vikunja

Classification

Weakness

CWE-770 Allocation of Resources Without Limits or Throttling

References

github.com /go-vikunja/vikunja/security/advisories/GHSA-3x3m-2j93-w46j
vendor-advisory, advisory
vulncheck.com /advisories/vikunja-before-2.7.1-memory-exhaustion-via-unbounded-avatar-size-cache
third-party-advisory

Sources

CVE List CVE-2026-123523
NVD CVE-2026-123523
Maintainer advisory GHSA-3x3m-2j93-w46j

Fencer Intel 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.

The maintainers of go-vikunja/vikunja published their own advisory on GitHub. Reviewed sources take precedence over it.