GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

FKIE_CVE-2026-21874

Vulnerability from fkie_nvd - Published: 2026-01-08 10:15 - Updated: 2026-06-17 10:19
Severity
5.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Summary
NiceGUI is a Python-based UI framework. From versions v2.10.0 to 3.4.1, an unauthenticated attacker can exhaust Redis connections by repeatedly opening and closing browser tabs on any NiceGUI application using Redis-backed storage. Connections are never released, leading to service degradation when Redis hits its connection limit. NiceGUI continues accepting new connections - errors are logged but the app stays up with broken storage functionality. This issue has been patched in version 3.5.0.
References
security-advisories@github.comhttps://github.com/zauberzeug/nicegui/commit/6c52eb2c90c4b67387c025b29646b4bc1578eb83Patch
security-advisories@github.comhttps://github.com/zauberzeug/nicegui/releases/tag/v3.5.0Release Notes
security-advisories@github.comhttps://github.com/zauberzeug/nicegui/security/advisories/GHSA-mp55-g7pj-rvm2Exploit, Vendor Advisory
134c704f-9b21-4f2e-91b3-4a467353bcc0https://github.com/zauberzeug/nicegui/security/advisories/GHSA-mp55-g7pj-rvm2Exploit, Vendor Advisory
Impacted products
Vendor Product Version
zauberzeug nicegui *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "nicegui",
          "vendor": "zauberzeug",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 2.10.0, \u003c 3.5.0"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:zauberzeug:nicegui:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "1FBD1A44-26D5-44F9-9D65-6654C756FB59",
              "versionEndExcluding": "3.5.0",
              "versionStartIncluding": "2.10.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "NiceGUI is a Python-based UI framework. From versions v2.10.0 to 3.4.1, an unauthenticated attacker can exhaust Redis connections by repeatedly opening and closing browser tabs on any NiceGUI application using Redis-backed storage. Connections are never released, leading to service degradation when Redis hits its connection limit. NiceGUI continues accepting new connections - errors are logged but the app stays up with broken storage functionality. This issue has been patched in version 3.5.0."
    },
    {
      "lang": "es",
      "value": "NiceGUI es un framework de interfaz de usuario (UI) basado en Python. Desde las versiones v2.10.0 hasta la 3.4.1, un atacante no autenticado puede agotar las conexiones de Redis abriendo y cerrando repetidamente pesta\u00f1as del navegador en cualquier aplicaci\u00f3n NiceGUI que utilice almacenamiento respaldado por Redis. Las conexiones nunca se liberan, lo que lleva a una degradaci\u00f3n del servicio cuando Redis alcanza su l\u00edmite de conexiones. NiceGUI sigue aceptando nuevas conexiones; se registran errores, pero la aplicaci\u00f3n permanece activa con una funcionalidad de almacenamiento rota. Este problema ha sido parcheado en la versi\u00f3n 3.5.0."
    }
  ],
  "id": "CVE-2026-21874",
  "lastModified": "2026-06-17T10:19:04.197",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 5.3,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 1.4,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-21874",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-01-08T14:43:46.386940Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-01-08T10:15:55.820",
  "references": [
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Patch"
      ],
      "url": "https://github.com/zauberzeug/nicegui/commit/6c52eb2c90c4b67387c025b29646b4bc1578eb83"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Release Notes"
      ],
      "url": "https://github.com/zauberzeug/nicegui/releases/tag/v3.5.0"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "url": "https://github.com/zauberzeug/nicegui/security/advisories/GHSA-mp55-g7pj-rvm2"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "url": "https://github.com/zauberzeug/nicegui/security/advisories/GHSA-mp55-g7pj-rvm2"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-772"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





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

Author Source Type Date Other

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.