CVE-2024-8387

Memory safety bugs present in Firefox 129, Firefox ESR 128.1, and Thunderbird 128.1. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 130, Firefox ESR < 128.2, and Thunderbird < 128.2.

Published: 2024-09-03 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2024-8387 is rated Moderate Risk (54.1/100): CVSS Critical severity, with low exploitation likelihood (EPSS 0.58%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2024-8387

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 0.80% 0.58% -0.21%
2 2026-05-06 0.54% 0.80% +0.25%
3 2026-01-23 — 0.54% —

Full EPSS history (16 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2024-8387

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2024-8387

OS Trackers for CVE-2024-8387

vendor priority summary link
alpine critical CVE-2024-8387: 3 source package rows (firefox, firefox-esr, thunderbird); 318 state rows across 3 repos (3.20-community, 3.22-community, edge-community); fixed 0, open 318. https://security.alpinelinux.org/vuln/CVE-2024-8387
debian unimportant CVE-2024-8387 unimportant priority: Debian including 2 source packages (firefox, thunderbird), 6 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 6. https://security-tracker.debian.org/tracker/CVE-2024-8387
gentoo high CVE-2024-8387: 3 GLSA(s) (202412-04, 202412-06, 202412-13), 5 atom(s) (dev-lang/spidermonkey, mail-client/thunderbird, mail-client/thunderbird-bin, www-client/firefox, www-client/firefox-bin); latest impact high. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2024-8387
redhat high — https://access.redhat.com/security/cve/CVE-2024-8387
suse high CVE-2024-8387 severity important: SUSE including 36 source package names (MozillaFirefox-128.2.0-112.225.1, MozillaFirefox-128.2.0-150200.152.149.1, …), 152 product×package rows across 52 product lines (Container suse/kiosk/firefox-esr, Image SLES12-SP5-SAP-Azure-LI-BYOS-Production, … (52 product lines)): Fixed 152. https://www.suse.com/security/cve/CVE-2024-8387/
ubuntu medium CVE-2024-8387 medium priority: Ubuntu including 9 source packages (firefox, mozjs102, …), 47 status rows across 6 suites (bionic, focal, jammy, noble, oracular, upstream): DNE 21, ignored 10, needs-triage 9, not-affected 6, released 1. https://ubuntu.com/security/CVE-2024-8387

Affected software / configurations for CVE-2024-8387

Vendor Product Version Raw CPE
mozilla firefox 129.0 cpe:2.3:a:mozilla:firefox:129.0:*:*:*:*:*:*:*
mozilla firefox_esr 128.1 cpe:2.3:a:mozilla:firefox_esr:128.1:*:*:*:*:*:*:*
mozilla thunderbird 128.1 cpe:2.3:a:mozilla:thunderbird:128.1:*:*:*:*:*:*:*

References for CVE-2024-8387

cvelogic Threat Intelligence