SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2017-5413

This vulnerability affects Firefox < 52 and Thunderbird < 52.

CRITICAL 9.8EPSS 1.83%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.83%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

A segmentation fault can occur during some bidirectional layout operations. This vulnerability affects Firefox < 52 and Thunderbird < 52.

CVSS 3.0
9.8 CRITICALCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
1.83% probability · 79th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-119
Affected
mozilla/firefox · mozilla/thunderbird
Source
security@mozilla.org
EPSS trend
0%3%5%27 October 2026: 1.83%27 October 202627 October 2026

EPSS 1.8% 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.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.