CVE-2024-8383

Firefox normally asks for confirmation before asking the operating system to find an application to handle a scheme that the browser does not support. It did not ask before doing so for the Usenet-related schemes news: and snews:. Since most operating systems don't have a trusted newsreader installed by default, an unscrupulous program that the user downloaded could register itself as a handler. The website that served the application download could then launch that application at will. This vulnerability affects Firefox < 130, Firefox ESR < 128.2, and Firefox ESR < 115.15.

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-2024-8383 is rated Moderate Risk (46.3/100): CVSS High severity, with low exploitation likelihood (EPSS 0.64%). 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-2024-8383

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 0.25% 0.64% +0.39%
2 2025-11-21 0.45% 0.25% -0.20%
3 2025-11-18 — 0.45% —

Full EPSS history (10 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2024-8383

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N 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:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 3.6 [email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N 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:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 3.6 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2024-8383

OS Trackers for CVE-2024-8383

vendor priority summary link
alpine — CVE-2024-8383: 3 source package rows (firefox, firefox-esr, thunderbird); 265 state rows across 3 repos (3.20-community, 3.22-community, edge-community); fixed 0, open 265. https://security.alpinelinux.org/vuln/CVE-2024-8383
debian not yet assigned CVE-2024-8383 not yet assigned priority: Debian including 3 source packages (firefox, firefox-esr, thunderbird), 8 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 8. https://security-tracker.debian.org/tracker/CVE-2024-8383
gentoo high CVE-2024-8383: 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-2024-8383
redhat medium — https://access.redhat.com/security/cve/CVE-2024-8383
suse high CVE-2024-8383 severity important: SUSE including 31 source package names (MozillaFirefox-128.2.0-112.225.1, MozillaFirefox-128.2.0-150200.152.149.1, …), 124 product×package rows across 46 product lines (Container suse/kiosk/firefox-esr, Image SLES12-SP5-SAP-Azure-LI-BYOS-Production, … (46 product lines)): Fixed 124. https://www.suse.com/security/cve/CVE-2024-8383/
ubuntu medium CVE-2024-8383 medium priority: Ubuntu including 9 source packages (firefox, mozjs102, …), 65 status rows across 8 suites (bionic, focal, jammy, noble, oracular, plucky, questing, upstream): DNE 34, needs-triage 11, not-affected 10, ignored 9, released 1. https://ubuntu.com/security/CVE-2024-8383

Affected software / configurations for CVE-2024-8383

Vendor Product Version Raw CPE
mozilla firefox < 130.0 cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
mozilla firefox_esr < 115.15 cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:*
mozilla firefox_esr >= 128.0, < 128.2 cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:*

References for CVE-2024-8383

cvelogic Threat Intelligence