SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2018-5097

A use-after-free vulnerability can occur during XSL transformations when the source document for the transformation is manipulated by script content during the transformation.

CRITICAL 9.8EPSS 7.03%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (7.03%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

A use-after-free vulnerability can occur during XSL transformations when the source document for the transformation is manipulated by script content during the transformation. This results in a potentially exploitable crash. This vulnerability affects Thunderbird < 52.6, Firefox ESR < 52.6, and Firefox < 58.

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
7.03% probability · 94th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-416
Affected
debian/debian linux · redhat/enterprise linux desktop · redhat/enterprise linux server · redhat/enterprise linux server aus · redhat/enterprise linux server eus · redhat/enterprise linux workstation · mozilla/firefox · mozilla/thunderbird · canonical/ubuntu linux
Source
security@mozilla.org
EPSS trend
0%5%10%27 October 2026: 7.03%27 October 202627 October 2026

EPSS 7.0% since 27 October 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

References

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