{
  "id": "CVE-2021-29991",
  "sourceIdentifier": "security@mozilla.org",
  "published": "2021-11-03T01:15:07.060",
  "lastModified": "2021-11-04T21:01:32.743",
  "vulnStatus": "Analyzed",
  "descriptions": [
    {
      "lang": "en",
      "value": "Firefox incorrectly accepted a newline in a HTTP/3 header, interpretting it as two separate headers. This allowed for a header splitting attack against servers using HTTP/3. This vulnerability affects Firefox < 91.0.1 and Thunderbird < 91.0.1."
    },
    {
      "lang": "es",
      "value": "Firefox aceptaba incorrectamente una nueva l\u00ednea en un encabezado HTTP/3, interpret\u00e1ndola como dos encabezados separados. Esto permit\u00eda un ataque de divisi\u00f3n de encabezados contra servidores que usaban HTTP/3. Esta vulnerabilidad afecta a Firefox versiones anteriores a 91.0.1 y Thunderbird versiones anteriores a 91.0.1"
    }
  ],
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          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "REQUIRED",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
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}