CVE-1999-0347

CRITICAL ⚠ Exploit

Internet Explorer 4.01 allows remote attackers to read local files and spoof web pages via a "%01" character in an "about:" Javascript URL, which causes Internet Explorer to use the domain specifie...

Affects 0 products across 1 vendor.

CVSS 2.010.0
EPSS7.5%
Percentile94th
PatchUnknown
CVSS Vector — Plain English Remotely exploitable over the network, low complexity.
◆ AI Analysis — automated analysis, not human-reviewed

Internet Explorer 4.01 is vulnerable to an attack that allows remote attackers to read local files and spoof web pages by using a '%01' character in an 'about:' Javascript URL.

BSID: BS-1999-GLOBAL-307793-C • Model: /workspace/models/qwen2.5-coder-32b-instruct-bf16 • Confidence: HIGH

Is this CVE in your environment?

BreachSpider monitors your ICS/OT environment for vulnerabilities like this one. No agents or network access required. Free to start.

Check My Environment →
Frequently Asked Questions
What is CVE-1999-0347?
Internet Explorer 4.01 is vulnerable to an attack that allows remote attackers to read local files and spoof web pages by using a '%01' character in an 'about:' Javascript URL.
What is the CVSS score for CVE-1999-0347?
CVE-1999-0347 has CVSS 10.0 (Critical). Vector: AV:N/AC:L/Au:N/C:C/I:C/A:C. EPSS: 7.5%.
Is CVE-1999-0347 actively exploited?
Public exploit available for CVE-1999-0347. Exploitation risk elevated.
How do I remediate CVE-1999-0347?
Priority: IMMEDIATE.
What systems are affected by CVE-1999-0347?
CVE-1999-0347 affects Javascript.
Vulnerability Details
CVE IDCVE-1999-0347
BSIDBS-1999-GLOBAL-307793-C BreachSpider Global ID
CVSS VectorAV:N/AC:L/Au:N/C:C/I:C/A:C
Published1999-01-26
Last Modified2026-06-16
ICS Relevance0%
SourceNVD
Official Description

Internet Explorer 4.01 allows remote attackers to read local files and spoof web pages via a "%01" character in an "about:" Javascript URL, which causes Internet Explorer to use the domain specified after the character.

Source: NIST NVD / MITRE CVE Database

Attack Vector Analysis — CITED Relevance

The vulnerability occurs when a '%01' character is inserted into an 'about:' URL, which manipulates the domain context, enabling unauthorized access to local files and the ability to spoof web pages.

Exploitation Likelihood: CRITICAL

Affected Products
VendorProductAffected Versions
Javascript — —
Remediation

No official vendor advisory link on record. See the CVE record →

Threat Intelligence
● Threat Intelligence Validated: October 2026 | Threat Age: 10132 Days
CISA known-exploitedNot in KEV catalog
Public Exploit⚠ Available — Reference
PoC CodeNot confirmed
AI Enrichment Record — provenance & audit hash
Model/workspace/models/qwen2.5-coder-32b-instruct-bf16
ConfidenceHIGH
Enriched At2026-05-24
Related CVEs affecting Javascript
CVE-2025-53624 10.0 The Docusaurus gists plugin adds a page to your Docusaurus instance, displayi... CVE-2025-61481 10.0 An issue in MikroTik RouterOS v.7.14.2 and SwOS v.2.18 exposes the WebFig man... CVE-2025-65108 10.0 md-to-pdf is a CLI tool for converting Markdown files to PDF using Node.js an... CVE-2026-40470 9.9 A critical XSS vulnerability affected hackage-server and hackage.haskell.org.... CVE-2025-8047 9.8 The disable-right-click-powered-by-pixterme through v1.2 and pixter-image-dig...
View all Javascript CVEs →

Critical Severity - Know Your Exposure

A CVSS 10.0 vulnerability in your ICS environment cannot wait. BreachSpider maps critical CVEs to your specific assets and tells you what to fix first.

Create a free account →