FKIE_CVE-2026-53524

Vulnerability from fkie_nvd - Published: 2026-08-21 23:16 - Updated: 2026-10-14 19:10
Severity
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Summary
WeeChat (Wee Enhanced Environment for Chat) is a free chat client. In versions 4.3.0 through 4.9.0, the WeeChat relay module's WebSocket permessage-deflate decompression function relay_websocket_inflate() has no upper bound on output size. An authenticated relay user can send a small compressed WebSocket frame (~100 bytes) that decompresses to gigabytes, exhausting all server memory and crashing the entire WeeChat process. The api protocol enables permessage-deflate and requires authentication before WebSocket upgrade. Version 4.9.1 patches the issue.
References
security-advisories@github.comhttps://github.com/weechat/weechat/security/advisories/GHSA-v2v4-45wm-5cr3
134c704f-9b21-4f2e-91b3-4a467353bcc0https://github.com/weechat/weechat/security/advisories/GHSA-v2v4-45wm-5cr3
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "weechat",
          "vendor": "weechat",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 4.3.0, \u003c 4.9.1"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "WeeChat (Wee Enhanced Environment for Chat) is a free chat client. In versions 4.3.0 through 4.9.0, the WeeChat relay module\u0027s WebSocket permessage-deflate decompression function relay_websocket_inflate() has no upper bound on output size. An authenticated relay user can send a small compressed WebSocket frame (~100 bytes) that decompresses to gigabytes, exhausting all server memory and crashing the entire WeeChat process. The api protocol enables permessage-deflate and requires authentication before WebSocket upgrade. Version 4.9.1 patches the issue."
    },
    {
      "lang": "es",
      "value": "WeeChat (Wee Enhanced Environment for Chat) es un cliente de chat gratuito. En las versiones 4.3.0 a 4.9.0, la funci\u00f3n de descompresi\u00f3n permessage-deflate de WebSocket del m\u00f3dulo de retransmisi\u00f3n de WeeChat, relay_websocket_inflate(), no tiene un l\u00edmite superior en el tama\u00f1o de salida. Un usuario de retransmisi\u00f3n autenticado puede enviar una peque\u00f1a trama WebSocket comprimida (~100 bytes) que se descomprime a gigabytes, agotando toda la memoria del servidor y bloqueando todo el proceso de WeeChat. El protocolo API habilita permessage-deflate y requiere autenticaci\u00f3n antes de la actualizaci\u00f3n de WebSocket. La versi\u00f3n 4.9.1 corrige el problema."
    }
  ],
  "id": "CVE-2026-53524",
  "lastModified": "2026-10-14T19:10:00.297",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 3.6,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-53524",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-08-24T20:09:05.967952Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-08-21T23:16:26.213",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/weechat/weechat/security/advisories/GHSA-v2v4-45wm-5cr3"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "url": "https://github.com/weechat/weechat/security/advisories/GHSA-v2v4-45wm-5cr3"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-409"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



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