SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2018-5159

An integer overflow can occur in the Skia library due to 32-bit integer use in an array without integer overflow checks, resulting in possible out-of-bounds writes.

EXPLOIT ✓CRITICAL 9.8EPSS 20.6%

Does this matter?

EPSS puts the probability of exploitation in the next 30 days at 20.6%, higher than 98% of all known CVEs. Patch or mitigate before the next change window.

Description

An integer overflow can occur in the Skia library due to 32-bit integer use in an array without integer overflow checks, resulting in possible out-of-bounds writes. This could lead to a potentially exploitable crash triggerable by web content. This vulnerability affects Thunderbird < 52.8, Thunderbird ESR < 52.8, Firefox < 60, and Firefox ESR < 52.8.

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
20.64% probability · 98th percentile
Public exploits
1 in Exploit-DB · verified · first 25 May 2018
CISA KEV
Not listed
Weakness
CWE-190, CWE-787
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 server tus · redhat/enterprise linux workstation · mozilla/firefox · mozilla/thunderbird · mozilla/thunderbird esr · canonical/ubuntu linux
Source
security@mozilla.org
EPSS trend
0%13%25%21 September 2026: 14.47%22 September 2026: 21.04%27 October 2026: 20.64%21 September 202627 October 2026

EPSS moved from 14.5% on 21 September 2026 to 20.6% on 27 October 2026, peaking at 21.0% on 22 September 2026. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”.

Public exploits (1)

Entries in Exploit-DB that cite this CVE. Links go to the Exploit-DB page and to the file in the public repository; nothing is hosted here. A verified tick means the Exploit-DB team confirmed the exploit works against the stated version.

EDB-IDTitleTypePublishedVerified
EDB-44759source ↗Skia and Firefox - Integer Overflow in SkTDArray Leading to Out-of-Bounds Writemultiple · Google Security Researchdos25 May 2018yes

References

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