Eventpoll Vulnerability in the Linux Kernel Affecting Multithreading Operations
CVE-2026-43074

7.8HIGH

Key Information:

Vendor

Linux

Status
Vendor
CVE Published:
6 May 2026

Badges

๐Ÿ‘พ Exploit Exists๐ŸŸก Public PoC

What is CVE-2026-43074?

A use-after-free vulnerability exists in the Linux kernel related to the eventpoll functionality, specifically during the execution of the ep_free() function in eventpoll.c. This flaw allows for the struct eventpoll to be deallocated while still being accessed by another thread, leading to potential instability and exploitation opportunities. The vulnerability is now mitigated by deferring the memory deallocation to an RCU (Read-Copy-Update) callback, ensuring that it is only freed when it is safe to do so. This enhancement significantly contributes to the stability and security of multithreaded applications utilizing the eventpoll subsystem.

Affected Version(s)

Linux f2451def095c1743adcfcb0cb5dadc86034e162a < 902120be4f44947df6311002addc7faf69bdbff1

Linux a1f93804449d13f97dabd4b996817de4bf1ed67a

Linux 58c9b016e12855286370dfb704c08498edbc857a

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

References

CVSS V3.1

Score:
7.8
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Local
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged

Timeline

  • ๐ŸŸก

    Public PoC available

  • ๐Ÿ‘พ

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

.