CVE-2018-5126

Severity: critical (CVSS 9.8 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.8% 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 58. 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 < 59.

Affected products

Canonical Ubuntu Linux: 14.04, 16.04, 17.10
Mozilla Firefox: before 59.0 — fixed in 59.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 59.0. Check the vendor advisory for mitigations.

References

http://www.securityfocus.com/bid/103386
http://www.securitytracker.com/id/1040514
https://bugzilla.mozilla.org/buglist.cgi?bug_id=1433671%2C1414768%2C1416523%2C1425691%2C1441006%2C1429768%2C1426002%2C1297740%2C1435566%2C1432855%2C1442318%2C1421963%2C1422631%2C1426603%2C1404297%2C1425257%2C1373934%2C1423173%2C1416940
https://usn.ubuntu.com/3596-1/
https://www.mozilla.org/security/advisories/mfsa2018-06/
http://www.securityfocus.com/bid/103386
http://www.securitytracker.com/id/1040514
https://bugzilla.mozilla.org/buglist.cgi?bug_id=1433671%2C1414768%2C1416523%2C1425691%2C1441006%2C1429768%2C1426002%2C1297740%2C1435566%2C1432855%2C1442318%2C1421963%2C1422631%2C1426603%2C1404297%2C1425257%2C1373934%2C1423173%2C1416940
https://usn.ubuntu.com/3596-1/
https://www.mozilla.org/security/advisories/mfsa2018-06/

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