CVE-2017-5456
CVSS v3
9.8
CRITICAL
EPSS Score
2.8 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
A mechanism to bypass file system access protections in the sandbox using the file system request constructor through an IPC message. This allows for read and write access to the local file system. This vulnerability affects Firefox ESR < 52.1 and Firefox < 53.
Technical details
- Published
- 2018-06-11
Frequently asked questions
What is CVE-2017-5456?
A mechanism to bypass file system access protections in the sandbox using the file system request constructor through an IPC message. This allows for read and write access to the local file system. This vulnerability affects Firefox ESR < 52.1 and Firefox < 53.
Is CVE-2017-5456 actively exploited?
Active exploitation of CVE-2017-5456 has not been confirmed. Its EPSS score was 2.8% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2017-5456?
CVE-2017-5456 has a CVSS v3 base score of 9.8 (CRITICAL severity).
Is CVE-2017-5456 affecting your environment?
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