CVE-2018-18493: canonical ubuntu_linux
Vulnerability summary
CVE-2018-18493 is a critical (CVSS 9.8) vulnerability in canonical ubuntu_linux. EPSS estimates a 4.98% chance of exploitation in the next 30 days, higher than 92.2% of scored vulnerabilities.
Severe, CVSS 9.8 (NVD); no exploitation reported by the 5 checked sources; EPSS 5% (FIRST, 03-11-2026)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 19 · Related 10Timeline
- 28-02-2019PublishedVulnerability first disclosed.
- 05-08-2024Last modifiedVulnerability information updated.
Description
A buffer overflow can occur in the Skia library during buffer offset calculations with hardware accelerated canvas 2D actions due to the use of 32-bit calculations instead of 64-bit. This results in a potentially exploitable crash. This vulnerability affects Thunderbird < 60.4, Firefox ESR < 60.4, and Firefox < 64.
CVSS metrics
4 scores · 3 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated9.8CriticalCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated9.8CriticalCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
4.98%
Chance of exploitation in the next 30 days
Percentile
92%
Versus all other CVEs
30-day change
No change 0.00 pp
From 4.98% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Redhat6 products
- enterprise_linux_desktop6.0 | 7.0
- enterprise_linux_server6.0 | 7.0
- enterprise_linux_server_aus7.6
- enterprise_linux_server_eus7.6
- enterprise_linux_server_tus7.6
Debian3 products
- firefox-esr< 60.4.0esr-1
- thunderbird< 1:60.4.0-1
- debian_linuxEOL8.0 | 9.0
Mozilla3 products
- firefox≥ unspecified, < 64 | < 60.4.0 | < 64.0
- firefox esr≥ unspecified, < 60.4
- thunderbird≥ unspecified, < 60.4 | < 60.4.0
Ubuntu2 products
- firefox< 64.0+build3-0ubuntu0.14.04.1 | < 64.0+build3-0ubuntu0.16.04.1 | < 64.0+build3-0ubuntu0.18.04.1
- thunderbird< 1:60.4.0+build2-0ubuntu0.14.04.1 | < 1:60.4.0+build2-0ubuntu0.16.04.1 | < 1:60.4.0+build2-0ubuntu0.18.04.1
Canonical1 product
- ubuntu_linuxEOL14.04 | 16.04 | 18.04 | 18.10
5 vendors · 15 products
References
22 links
lists.debian.org/debian-lts-announce/2018/12/msg00002.htmlMailing ListX Refsource MLISTThird Party Advisory
Show all 22 references
- bugzilla.mozilla.org/show_bug.cgi?id=1504452X Refsource CONFIRMIssue TrackingPermissions RequiredVendor Advisory