An earlier fix for an Inter-process Communication (IPC) vulnerability, CVE-2011-3079, added authentication to communication between IPC endpoints and server parents during IPC process creation. This authentication is insufficient for channels created after the IPC process is started, leading to the authentication not being correctly applied to later channels. This could allow for a sandbox escape through IPC channels due to lack of message validation in the listener process. This vulnerability affects Thunderbird < 60.5, Firefox ESR < 60.5, and Firefox < 65.
Conclusion & alert: CVE-2018-18505 is rated High Risk (74.1/100): CVSS Critical severity, with high exploitation likelihood (EPSS 4.54%, 90th percentile). Core evidence: EPSS ranks this CVE among the most likely to be exploited in the near term. EPSS rose +2.49% over the last day, indicating growing attacker interest. Mandatory action: High exploitation likelihood—assess exposure and prioritize remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-06-15 | 2.04% | 4.54% | +2.49% |
| 2 | 2026-05-29 | 3.18% | 2.04% | -1.14% |
| 3 | 2026-05-26 | — | 3.18% | — |
Full EPSS history (26 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 10.0 | 3.0 | CRITICAL |
|
3.9 | 6.0 | [email protected] |
| 7.5 | 2.0 | HIGH |
|
10.0 | 6.4 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
alpine
|
— | CVE-2018-18505: 1 source package rows (firefox-esr); 7 state rows across 7 repos (3.17-community, 3.18-community, 3.19-community, 3.20-community, 3.21-community, 3.22-community, edge-community); fixed 7, open 0. | https://security.alpinelinux.org/vuln/CVE-2018-18505 |
debian
|
not yet assigned | CVE-2018-18505 not yet assigned priority: Debian including 3 source packages (firefox, firefox-esr, thunderbird), 11 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 11. | https://security-tracker.debian.org/tracker/CVE-2018-18505 |
gentoo
|
normal | CVE-2018-18505: 2 GLSA(s) (201903-04, 201904-07), 4 atom(s) (mail-client/thunderbird, mail-client/thunderbird-bin, www-client/firefox, www-client/firefox-bin); latest impact normal. | https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2018-18505 |
redhat
|
high | — | https://access.redhat.com/security/cve/CVE-2018-18505 |
suse
|
medium | CVE-2018-18505 severity moderate: SUSE including 184 source package names (1.0.0.1862.1.5.2:libfreebl3-3.41.1-3.13.1, 1.0.0.1862.1.5.2:libsoftokn3-3.41.1-3.13.1, …), 743 product×package rows across 122 product lines (Container bci/openjdk, Container bci/openjdk-devel, … (122 product lines)): Fixed 694, Known Not Affected 49. | https://www.suse.com/security/cve/CVE-2018-18505/ |
ubuntu
|
medium | CVE-2018-18505 medium priority: Ubuntu including 5 source packages (firefox, mozjs38, mozjs52, mozjs60, thunderbird), 80 status rows across 16 suites (bionic, cosmic, disco, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, trusty, upstream, xenial): DNE 35, released 32, ignored 13. | https://ubuntu.com/security/CVE-2018-18505 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| mozilla | firefox | < 60.5.0 | cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:* |
| mozilla | firefox | < 65.0 | cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:* |
| mozilla | thunderbird | < 60.5.0 | cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* |
| canonical | ubuntu_linux | 14.04 | cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:* |
| canonical | ubuntu_linux | 16.04 | cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:* |
| canonical | ubuntu_linux | 18.04 | cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:* |
| canonical | ubuntu_linux | 18.10 | cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:* |
| debian | debian_linux | 8.0 | cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:* |
| debian | debian_linux | 9.0 | cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* |
| redhat | enterprise_linux_desktop | 6.0 | cpe:2.3:o:redhat:enterprise_linux_desktop:6.0:*:*:*:*:*:*:* |
| redhat | enterprise_linux_desktop | 7.0 | cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:* |
| redhat | enterprise_linux_server | 6.0 | cpe:2.3:o:redhat:enterprise_linux_server:6.0:*:*:*:*:*:*:* |
| redhat | enterprise_linux_server | 7.0 | cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:* |
| redhat | enterprise_linux_server_aus | 7.6 | cpe:2.3:o:redhat:enterprise_linux_server_aus:7.6:*:*:*:*:*:*:* |
| redhat | enterprise_linux_server_eus | 7.6 | cpe:2.3:o:redhat:enterprise_linux_server_eus:7.6:*:*:*:*:*:*:* |
| redhat | enterprise_linux_server_tus | 7.6 | cpe:2.3:o:redhat:enterprise_linux_server_tus:7.6:*:*:*:*:*:*:* |
| redhat | enterprise_linux_workstation | 6.0 | cpe:2.3:o:redhat:enterprise_linux_workstation:6.0:*:*:*:*:*:*:* |
| redhat | enterprise_linux_workstation | 7.0 | cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:* |