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CVE-2026-91971 (GCVE-0-2026-91971)

Vulnerability from cvelistv5 – Published: 2026-09-15 15:18 – Updated: 2026-09-15 15:18
VLAI
Title
Vikunja before 2.6.0 Denial of Service via Avatar Upload
Summary
Vikunja before 2.6.0 fails to apply pixel decode limits to avatar and project-background upload endpoints, allowing authenticated users to upload crafted images that decode to excessive pixel counts. Attackers can upload small images with extreme aspect ratios that consume significant CPU and memory during processing, causing denial of service through repeated or concurrent uploads.
Severity
7.1 (High)
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
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-400 - Uncontrolled Resource Consumption
Assigner
References
Impacted products
Vendor Product Version CPE status
go-vikunja vikunja Affected: 0 , < 2.6.0 (semver)
Unaffected: 2.6.0 (semver)
    cpe:2.3:a:vikunja:vikunja:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-08-31 00:00
Credits
Str1ckl4nd 7thParkk JellowBeanz26
Show details on NVD website
To clipboard 

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        }
      ],
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            "Recovery": "NOT_DEFINED",
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            "privilegesRequired": "LOW",
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            "userInteraction": "NONE",
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          "name": "GitHub Security Advisory (GHSA-4vh2-39rq-rq8j)",
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    "datePublished": "2026-09-15T15:18:22.129Z",
    "dateReserved": "2026-09-15T11:09:54.873Z",
    "dateUpdated": "2026-09-15T15:18:22.129Z",
    "state": "PUBLISHED"
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  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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