What’s Vulnerable › Vulnerabilities

CVE-2018-5096

• Severity: critical (CVSS 9.8 v3.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.9% 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-416

Description

A use-after-free vulnerability can occur while editing events in form elements on a page, resulting in a potentially exploitable crash. This vulnerability affects Firefox ESR < 52.6 and Thunderbird < 52.6.

Affected products

• Debian Linux: 7.0, 8.0, 9.0
• Mozilla Firefox: before 52.6.0 — fixed in 52.6.0
• Mozilla Thunderbird: before 52.6.0 — fixed in 52.6.0
• Red Hat Enterprise Linux: 6.0, 7.0
• RedHat Enterprise Linux Desktop: 6.0, 7.0
• RedHat Enterprise Linux Server: 6.0, 7.0
• RedHat Enterprise Linux Server Aus: 7.4
• RedHat Enterprise Linux Server Eus: 7.4, 7.5
• RedHat Enterprise Linux Workstation: 6.0, 7.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 52.6.0; Mozilla Thunderbird 52.6.0. Check the vendor advisory for mitigations.

References

• http://www.securityfocus.com/bid/102771
• https://access.redhat.com/errata/RHSA-2018:0122
• https://access.redhat.com/errata/RHSA-2018:0262
• https://bugzilla.mozilla.org/show_bug.cgi?id=1418922
• https://lists.debian.org/debian-lts-announce/2018/01/msg00030.html
• https://lists.debian.org/debian-lts-announce/2018/01/msg00036.html
• https://www.debian.org/security/2018/dsa-4096
• https://www.debian.org/security/2018/dsa-4102
• https://www.mozilla.org/security/advisories/mfsa2018-03/
• https://www.mozilla.org/security/advisories/mfsa2018-04/
• http://www.securityfocus.com/bid/102771
• https://access.redhat.com/errata/RHSA-2018:0122

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