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CVE-2026-91979 (GCVE-0-2026-91979)

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 Decompression Bomb
Summary
Vikunja before 2.6.0 fails to limit archive expansion during data import, allowing authenticated users to cause denial of service. Attackers can upload highly compressed files that expand to tens of gigabytes in memory and disk, exhausting server resources and crashing the instance.
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
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
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 0xcelien JellowBeanz26
Show details on NVD website
To clipboard 

{
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        {
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              "version": "0",
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            },
            {
              "status": "unaffected",
              "version": "2.6.0",
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            }
          ]
        }
      ],
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          "type": "reporter",
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          "type": "reporter",
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        },
        {
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          "type": "reporter",
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        }
      ],
      "datePublic": "2026-08-31T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "Vikunja before 2.6.0 fails to limit archive expansion during data import, allowing authenticated users to cause denial of service. Attackers can upload highly compressed files that expand to tens of gigabytes in memory and disk, exhausting server resources and crashing the instance."
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      "metrics": [
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            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
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            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
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            "userInteraction": "NONE",
            "vectorString": "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",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE"
          },
          "format": "CVSS"
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      "problemTypes": [
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          "descriptions": [
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              "description": "Uncontrolled Resource Consumption",
              "lang": "en",
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        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
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          "name": "GitHub Security Advisory (GHSA-w7jp-mf2v-8342)",
          "tags": [
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          "url": "https://github.com/go-vikunja/vikunja/security/advisories/GHSA-w7jp-mf2v-8342"
        },
        {
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          "tags": [
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        }
      ],
      "title": "Vikunja before 2.6.0 Denial of Service via Decompression Bomb",
      "x_generator": {
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  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-91979",
    "datePublished": "2026-09-15T15:18:24.176Z",
    "dateReserved": "2026-09-15T11:10:41.353Z",
    "dateUpdated": "2026-09-15T15:18:24.176Z",
    "state": "PUBLISHED"
  },
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      "percentile": "0.27135"
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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.

Sightings

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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.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • 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.


Detection rules are retrieved from Rulezet.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.