CVE Intelligence
High Logic error

CVE-2024-4367 — PDF.js vulnerable to arbitrary JavaScript execution upon opening a malicious PDF

A type check was missing when handling fonts in PDF.js, which would allow arbitrary JavaScript execution in the PDF.js context. This vulnerability affects Firefox < 126, Firefox ESR < 115.11, and Thunderbird < 115.11.

Published May 14, 2024 · Updated Oct 18, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: mozilla

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

Exploit-DB · 1
How the score was calculated
  • Public exploit/PoC (exploitdb)+8
  • EPSS 70.7% (30-day exploitation probability)+15
  • Technical severity (high)+6
  • CISA SSVC: exploitation "poc"+5

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
70.66%
ahead of 99% of scored CVEs · Oct 18, 2026
Affects
Debian
Debian Linux and 5 more
CVSS base
8.8
High · 4 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
Proof of concept
none · proof-of-concept · active
Automatable
No
can an attacker script the kill-chain steps
Technical impact
Total
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

  • Npm Pdfjs-dist: fixed in version 4.2.67 — github.com (GitHub Security Advisories)

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Debian Debian Linux, Mozilla Firefox, Mozilla Firefox ESR…).
  2. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  3. Apply the fixed version or the patch documented under Remediation.
  4. Exploitation requires user interaction: tighten email/web filtering and warn affected users.
  5. EPSS ahead of 99% of scored CVEs: prioritize it in the patch queue.
  6. Search available logs for exploit probes matching the vulnerability class (logic error), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Debian Debian Linux version 10.0 Vulnerable NIST National Vulnerability Database
Mozilla Firefox < 115.11.0< 126.0 Vulnerable NIST National Vulnerability Database
Mozilla Firefox < 126 Vulnerable CVE Program (cve.org) e CISA ADP
Mozilla Firefox ESR < 115.11 Vulnerable CVE Program (cve.org) e CISA ADP
Mozilla Thunderbird < 115.11.0 Vulnerable NIST National Vulnerability Database
Mozilla Thunderbird < 115.11 Vulnerable CVE Program (cve.org) e CISA ADP
Open-Xchange GmbH Open-xchange Appsuite Frontend version 7.10.6-revision27version 7.10.6-revision31version 7.10.6-revision30version 7.10.6-revision32version 7.10.6-revision33version 7.10.6-revision34version 7.10.6-revision35version 7.10.6-revision36
and 36 more version 7.10.6-revision37version 7.10.6-revision38version 7.10.6-revision39version 7.10.6-revision4version 7.10.6-revision40version 7.10.6-revision41version 7.10.6-revision42version 7.10.6-revision43version 7.10.6-revision44version 7.10.6-revision5version 7.10.6-revision6version 7.10.6-revision7version 7.10.6-revision8version 7.10.6-revision9version 7.10.6-revision29< 7.10.6version 7.10.6version 7.10.6-revision10version 7.10.6-revision11version 7.10.6-revision12version 7.10.6-revision13version 7.10.6-revision14version 7.10.6-revision15version 7.10.6-revision16version 7.10.6-revision17version 7.10.6-revision18version 7.10.6-revision19version 7.10.6-revision20version 7.10.6-revision21version 7.10.6-revision22version 7.10.6-revision23version 7.10.6-revision24version 7.10.6-revision25version 7.10.6-revision26version 7.10.6-revision28version 7.10.6-revision3
Vulnerable NIST National Vulnerability Database
Npm Pdfjs-dist ≤ 4.1.392 Vulnerable GitHub Security Advisories

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
8.8 CVSS 3.1 High 2.8 5.9 nvd@nist.gov via NIST National Vulnerability Database
8.8 CVSS 3.1 High — — GitHub, Inc. via GitHub Security Advisories
5.6 CVSS 3.1 Medium 2.2 3.4 134c704f-9b21-4f2e-91b3-4a467353bcc0 via NIST National Vulnerability Database
5.6 CVSS 3.1 Medium — — CISA-ADP via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H (score shown at the top: nvd@nist.gov)
Scoring entities (NIST, CNA, ADP) score independently; each score is shown with its origin. For prioritization we use 8.8 (NVD (NIST)) as a conservative provisional reference — not a definitive official score.

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-754 · Improper Check for Unusual or Exceptional Conditions

Other CVEs with this weakness →

Public exploits, PoCs and detection templates

Public code that demonstrates or tests the flaw raises the odds of mass exploitation — and Nuclei templates help find vulnerable assets in your environment.

Exploit-DB

Warning: public PoCs are sometimes disguised malware. Use them only for authorized testing in an isolated environment. This portal does not host exploit code — it only points to the sources.

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
web/proxy/WAF logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first.

  • 2026
  • Fix documented
    Oct 18, 2026 · GitHub Security Advisories
  • Affected products added · npm/pdfjs-dist
    Oct 18, 2026 · GitHub Security Advisories
  • Affected products added · mozilla/firefox, mozilla/firefox esr, mozilla/thunderbird
    Oct 18, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 18, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 18, 2026
  • Affected products added · mozilla/firefox, mozilla/thunderbird, debian/debian linux, open-xchange/open-xchange appsuite frontend
    Oct 18, 2026 · NIST National Vulnerability Database
  • CVSS changed · 8.8
    Oct 18, 2026 · NIST National Vulnerability Database
  • Source status changed · → Modified
    Oct 18, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 18, 2026 · Alertas do Telegram
  • 2024
  • CVE published
    May 14, 2024 · mozilla

Source activity

Repeated readings are counted rather than listed.

  • 2× References added · Oct 18, 2026 – Oct 18, 2026
  • 1× Official description updated · Oct 18, 2026 – Oct 18, 2026

References

21 on the record

Elsewhere on this site

Debian
every CVE for this vendor
Logic error
same class
CWE-754
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-106016 Mitigation bypass in the File Handling component 12d
  • CVE-2026-103500 Heap buffer overflow opening large email 18d
  • CVE-2026-96869 Information disclosure in the Networking component 19d
  • CVE-2026-100831 Use-after-free in the DOM: UI Events & Focus Handling component 19d
  • CVE-2026-100829 Mitigation bypass in the DOM: Security component 19d
  • CVE-2026-100832 Use-after-free in the Graphics: Canvas2D component 19d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2024-4367 is "PDF.js vulnerable to arbitrary JavaScript execution upon opening a malicious PDF", rated High. It affects Debian Linux (Debian); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 8.8 describes technical severity. EPSS 70.66% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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