CVE-2018-5178

What it is

A buffer overflow was found during UTF8 to Unicode string conversion within JavaScript with extremely large amounts of data. This vulnerability requires the use of a malicious or vulnerable legacy extension in order to occur. This vulnerability affects Thunderbird ESR < 52.8, Thunderbird < 52.8, and Firefox ESR < 52.8.

At a glance

Exploitability

Can be exploited over the network without logging in. High risk of data exposure, data tampering, service disruption.

Exploit odds

4.9% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2018-06-11 21:29 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 01:59 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 4.9% in the next 30 days (EPSS).
• Severity: 8.1 HIGH (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2018-06-11 21:29 UTC

Last modified

2026-06-17 01:59 UTC

Exploit probability

4.9% · EPSS, next 30 days

Weakness

CWE-119 · Buffer errors

Record status

Modified

Affected

• Debian Linux 7.0
• Debian Linux 8.0
• Debian Linux 9.0
• Mozilla Firefox < 52.8.0
• Mozilla Thunderbird < 52.8.0
• Mozilla Thunderbird Esr < 52.8.0
• Canonical Ubuntu Linux 14.04
• Canonical Ubuntu Linux 16.04

Attack profile CVSS 3.0 · 8.1

Attack vector

Network

Complexity

High

Privileges needed

None

User interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2018-5178.md and follow it. Check whether this project is affected by CVE-2018-5178. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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