CVE-2024-0743

An unchecked return value in TLS handshake code could have caused a potentially exploitable crash. This vulnerability affects Firefox < 122, Firefox ESR < 115.9, and Thunderbird < 115.9.

Published: 2024-01-23 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2024-0743 is rated Moderate Risk (53.7/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.30%). 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-2024-0743

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 0.89% 1.30% +0.40%
2 2026-06-02 1.57% 0.89% -0.68%
3 2026-05-06 — 1.57% —

Full EPSS history (16 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2024-0743

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:N/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:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 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:N/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:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2024-0743

OS Trackers for CVE-2024-0743

vendor priority summary link
alpine — CVE-2024-0743: 3 source package rows (firefox, firefox-esr, thunderbird); 278 state rows across 3 repos (3.19-community, 3.22-community, edge-community); fixed 1, open 277. https://security.alpinelinux.org/vuln/CVE-2024-0743
debian not yet assigned CVE-2024-0743 not yet assigned priority: Debian including 4 source packages (firefox, firefox-esr, nss, thunderbird), 16 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 16. https://security-tracker.debian.org/tracker/CVE-2024-0743
gentoo high CVE-2024-0743: 1 GLSA(s) (202402-26), 2 atom(s) (www-client/firefox, www-client/firefox-bin); latest impact high. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2024-0743
redhat high — https://access.redhat.com/security/cve/CVE-2024-0743
suse high CVE-2024-0743 severity important: SUSE including 36 source package names (MozillaFirefox-115.9.0-112.203.2, MozillaFirefox-115.9.1-150200.152.131.1, …), 147 product×package rows across 54 product lines (Container suse/kiosk/firefox-esr, Image SLES12-SP5-SAP-Azure-LI-BYOS-Production, … (54 product lines)): Fixed 147. https://www.suse.com/security/cve/CVE-2024-0743/
ubuntu medium CVE-2024-0743 medium priority: Ubuntu including 8 source packages (firefox, mozjs102, …), 72 status rows across 9 suites (bionic, focal, jammy, lunar, mantic, noble, trusty, upstream, xenial): DNE 37, ignored 25, not-affected 4, released 4, needs-triage 2. https://ubuntu.com/security/CVE-2024-0743

Affected software / configurations for CVE-2024-0743

Vendor Product Version Raw CPE
mozilla firefox < 122.0 cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*

References for CVE-2024-0743

cvelogic Threat Intelligence