CVE-2019-8956

Description

In the Linux Kernel before versions 4.20.8 and 4.19.21 a use-after-free error in the "sctp_sendmsg()" function (net/sctp/socket.c) when handling SCTP_SENDALL flag can be exploited to corrupt memory.

Affected products

Vendor	Product	Affected	Fixed
—	Linux Kernel	4.20.x prior to 4.20.8, 4.19.x prior to 4.19.21	—

Fixed in Linux distributions

Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.

Debian

Security tracker ↗

Release	Package	Fixed in	Advisory
Debian 14	linux	4.19.28-1	—
Debian 13	linux	4.19.28-1	—
Debian 12	linux	4.19.28-1	—

Ubuntu

Security tracker ↗

Release	Package	Fixed in	Advisory
Ubuntu 18.04 LTS	linux-azure	4.18.0-1014.14~18.04.1	USN-3930-2
Ubuntu 18.04 LTS	linux-gcp-edge	4.18.0-1008.9~18.04.1	—
Ubuntu 18.04 LTS	linux-hwe	4.18.0-17.18~18.04.1	USN-3930-2

Public exploits

Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.

Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.

GitHub 1 repository

butterflyhack/CVE-2019-8956 ★ 8 · May 28, 2019

sctp-PoC

Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.

Advisories 1

USN-3930-2 linux-hwe, linux-azure vulnerabilities Ubuntu Security Notices (USN) · Sep 7, 2026

In the Linux Kernel before versions 4.20.8 and 4.19.21 a use-after-free error in the "sctp_sendmsg()" function (net/sctp/socket.c) when han…