CVE-2016-1939

Status: ModifiedMedium (5.3)—

Mozilla Firefox before 44.0 stores cookies with names containing vertical tab characters, which allows remote attackers to obtain sensitive information by reading HTTP Cookie headers. NOTE: this vulnerability exists because of an incomplete fix for CVE-2015-7208.

CVSS

Version: 3.0
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Base score: 5.3

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 1.76%
Percentile among all scored CVEs: 77
Score date: 10/11/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (3)

Mozilla — Firefox Opensuse — Leap Opensuse — Opensuse

CWEs

CWE-200

References

Raw JSON (NVD)

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{
  "id": "CVE-2016-1939",
  "cveTags": [],
  "metrics": {
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          "baseScore": 5,
          "accessVector": "NETWORK",
          "vectorString": "AV:N/AC:L/Au:N/C:P/I:N/A:N",
          "authentication": "NONE",
          "integrityImpact": "NONE",
          "accessComplexity": "LOW",
          "availabilityImpact": "NONE",
          "confidentialityImpact": "PARTIAL"
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        "acInsufInfo": false,
        "impactScore": 2.9,
        "baseSeverity": "MEDIUM",
        "obtainAllPrivilege": false,
        "exploitabilityScore": 10,
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          "baseSeverity": "MEDIUM",
          "vectorString": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "LOW"
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        "impactScore": 1.4,
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  "published": "2016-01-31T18:59:06.027",
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      "url": "http://lists.opensuse.org/opensuse-security-announce/2016-02/msg00001.html",
      "source": "security@mozilla.org"
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      "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1233784",
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    {
      "url": "https://security.gentoo.org/glsa/201605-06",
      "source": "security@mozilla.org"
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      "url": "http://www.ubuntu.com/usn/USN-2880-2",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
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    {
      "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1233784",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
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      "url": "https://security.gentoo.org/glsa/201605-06",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
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  "vulnStatus": "Modified",
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      "description": [
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          "value": "CWE-200"
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  ],
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    {
      "lang": "en",
      "value": "Mozilla Firefox before 44.0 stores cookies with names containing vertical tab characters, which allows remote attackers to obtain sensitive information by reading HTTP Cookie headers.  NOTE: this vulnerability exists because of an incomplete fix for CVE-2015-7208."
    },
    {
      "lang": "es",
      "value": "Mozilla Firefox en versiones anteriores a 44.0 almacena cookies con nombres que contienen caracteres de tabulación verticales, lo que permite a atacantes remotos obtener información sensible mediante la lectura de cabeceras HTTP Cookie. NOTA: esta vulnerabilidad existe debido a una solución incompleta para CVE-2015-7208."
    }
  ],
  "lastModified": "2026-06-17T00:42:54.047",
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}