CVE-2021-1748

HIGH

iPadOS < 14.4 - Remote Code Execution via Malicious URL Processing

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 2 public exploits for CVE-2021-1748. PoCs published by ChiChou, Ivanhoe76zzzz.

AI-analyzed exploit summary This repository provides a technical analysis and a patch backport for CVE-2021-1748, which involves arbitrary data URI handling in iOS WebViews. The README explains the root cause and limitations of the patch, while the Makefile outlines the build process for a tweak to mitigate the vulnerability.

Description

A validation issue was addressed with improved input sanitization. This issue is fixed in tvOS 14.4, watchOS 7.3, iOS 14.4 and iPadOS 14.4. Processing a maliciously crafted URL may lead to arbitrary javascript code execution.

Exploits (2)

nomisec WRITEUP 21 stars
by ChiChou · poc
https://github.com/ChiChou/mistune-patch-backport

This repository provides a technical analysis and a patch backport for CVE-2021-1748, which involves arbitrary data URI handling in iOS WebViews. The README explains the root cause and limitations of the patch, while the Makefile outlines the build process for a tweak to mitigate the vulnerability.

Classification
Writeup 90%
Attack Type
Xss
Complexity
Moderate
Reliability
Reliable
Target: iOS <= 14.3
No auth needed
Prerequisites: Access to a vulnerable iOS device · Ability to install tweaks (e.g., via jailbreak)
devstral-2 · analyzed Feb 18, 2026 Full analysis →
nomisec NO CODE 1 stars
by Ivanhoe76zzzz · poc
https://github.com/Ivanhoe76zzzz/itmsBlock

References (3)

Core 3
Core References
Release Notes, Vendor Advisory x_refsource_misc
https://support.apple.com/en-us/HT212146
Release Notes, Vendor Advisory x_refsource_misc
https://support.apple.com/en-us/HT212148
Release Notes, Vendor Advisory x_refsource_misc
https://support.apple.com/en-us/HT212149

Scores

CVSS v3 8.8
EPSS 0.0274
EPSS Percentile 84.3%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Details

CWE
CWE-20
Status published
Products (4)
apple/ipados < 14.4
apple/iphone_os < 14.4
apple/tvos < 14.4
apple/watchos < 7.3
Published Apr 02, 2021
Tracked Since Feb 18, 2026