CVE-2017-7755

Status: ModifiedHigh (7.8)—

The Firefox installer on Windows can be made to load malicious DLL files stored in the same directory as the installer when it is run. This allows privileged execution if the installer is run with elevated privileges. Note: This attack only affects Windows operating systems. Other operating systems are unaffected. This vulnerability affects Firefox < 54, Firefox ESR < 52.2, and Thunderbird < 52.2.

CVSS

Version: 3.0
Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Base score: 7.8

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 1.39%
Percentile among all scored CVEs: 71
Score date: 10/9/2026

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 (2)

Mozilla — Firefox Mozilla — Thunderbird

CWEs

CWE-426

References

Raw JSON (NVD)

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    },
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    }
  ],
  "lastModified": "2026-06-17T01:25:07.850",
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