CVE-2017-7813
This usually results in a non-exploitable crash, but can leak a limited amount of information from memory if it matches JavaScript identifier syntax.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.56%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Inside the JavaScript parser, a cast of an integer to a narrower type can result in data read from outside the buffer being parsed. This usually results in a non-exploitable crash, but can leak a limited amount of information from memory if it matches JavaScript identifier syntax. This vulnerability affects Firefox < 56.
- CVSS 3.0
- 8.2 HIGHCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H
- EPSS
- 1.56% probability · 75th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-125, CWE-704
- Affected
- mozilla/firefox
- Source
- security@mozilla.org
EPSS 1.6% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://www.securityfocus.com/bid/101057Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1039465Third Party Advisory, VDB Entry
- https://bugzilla.mozilla.org/show_bug.cgi?id=1383951Exploit, Issue Tracking
- https://www.mozilla.org/security/advisories/mfsa2017-21/Vendor Advisory
- http://www.securityfocus.com/bid/101057Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1039465Third Party Advisory, VDB Entry
- https://bugzilla.mozilla.org/show_bug.cgi?id=1383951Exploit, Issue Tracking
- https://www.mozilla.org/security/advisories/mfsa2017-21/Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.