CVE-2017-5399

Severity: critical (CVSS 9.8 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2018-06-11 · updated 2026-06-17
Weakness: CWE-119

Description

Memory safety bugs were reported in Firefox 51. Some of these bugs showed evidence of memory corruption and we presume that with enough effort that some of these could be exploited to run arbitrary code. This vulnerability affects Firefox < 52 and Thunderbird < 52.

Affected products

Mozilla Firefox: before 52.0 — fixed in 52.0
Mozilla Thunderbird: before 52.0 — fixed in 52.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 52.0; Mozilla Thunderbird 52.0. Check the vendor advisory for mitigations.

References

http://www.securityfocus.com/bid/96692
http://www.securitytracker.com/id/1037966
https://bugzilla.mozilla.org/buglist.cgi?bug_id=1332569%2C1315248%2C1261335%2C1321038%2C1331771%2C1339566%2C1339591%2C1240893%2C1341905%2C1323241%2C1336467%2C1270288%2C1295299%2C1296024%2C1304201%2C1306142%2C1307557%2C1308036%2C1334246%2C1334290%2C1317085%2C1339116%2C1324000%2C1323150%2C1332501%2C1320894%2C1333752%2C1303713%2C1321566%2C1264053%2C1343513
https://www.mozilla.org/security/advisories/mfsa2017-05/
https://www.mozilla.org/security/advisories/mfsa2017-09/
http://www.securityfocus.com/bid/96692
http://www.securitytracker.com/id/1037966
https://bugzilla.mozilla.org/buglist.cgi?bug_id=1332569%2C1315248%2C1261335%2C1321038%2C1331771%2C1339566%2C1339591%2C1240893%2C1341905%2C1323241%2C1336467%2C1270288%2C1295299%2C1296024%2C1304201%2C1306142%2C1307557%2C1308036%2C1334246%2C1334290%2C1317085%2C1339116%2C1324000%2C1323150%2C1332501%2C1320894%2C1333752%2C1303713%2C1321566%2C1264053%2C1343513
https://www.mozilla.org/security/advisories/mfsa2017-05/
https://www.mozilla.org/security/advisories/mfsa2017-09/

Get alerted when CVE-2017-5399 or the next vulnerability affects your stack