CVE-2025-43504

MEDIUM

Xcode < 26.1 - Denial of Service via Buffer Overflow

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2025-43504. PoCs published by calysteon.

AI-analyzed exploit summary This repository contains a proof-of-concept exploit for CVE-2025-43504, a pre-authentication global buffer overflow in LLDB's debugserver. The vulnerability allows remote attackers to overflow a static buffer by sending a maliciously crafted `qSpeedTest` packet, leading to potential denial-of-service or further exploitation.

Description

A buffer overflow was addressed with improved bounds checking. This issue is fixed in Xcode 26.1. A user in a privileged network position may be able to cause a denial-of-service.

Exploits (1)

nomisec WORKING POC
by calysteon · poc
https://github.com/calysteon/CVE-2025-43504

This repository contains a proof-of-concept exploit for CVE-2025-43504, a pre-authentication global buffer overflow in LLDB's debugserver. The vulnerability allows remote attackers to overflow a static buffer by sending a maliciously crafted `qSpeedTest` packet, leading to potential denial-of-service or further exploitation.

Classification
Working Poc 95%
Attack Type
Dos
Complexity
Moderate
Reliability
Reliable
Target: LLDB debugserver (pre-patched versions)
No auth needed
Prerequisites: Access to an iOS device with debugserver running and a Developer Disk Image mounted
devstral-2 · analyzed Feb 16, 2026 Full analysis →

References (1)

Core 1
Core References
Release Notes, Vendor Advisory
https://support.apple.com/en-us/125641

Scores

CVSS v3 4.9
EPSS 0.0031
EPSS Percentile 22.0%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-119
Status published
Products (2)
apple/xcode < 26.1
Apple/Xcode < 26.1
Published Nov 04, 2025
Tracked Since Feb 18, 2026