What’s Vulnerable › Vulnerabilities

CVE-2019-8956

• Severity: high (CVSS 7.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.1% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2019-04-01 · updated 2026-06-17
• Weakness: CWE-416

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

• Canonical Ubuntu Linux: 18.04, 18.10
• Linux kernel: from 4.17 before 4.19.21; from 4.20 before 4.20.8 — fixed in 4.19.21, 4.20.8

How to fix

Upgrade to a fixed version: Linux kernel 4.19.21, 4.20.8. Check the vendor advisory for mitigations.

References

• https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.21
• https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.20.8
• https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/?id=ba59fb0273076637f0add4311faa990a5eec27c0
• https://secuniaresearch.flexerasoftware.com/secunia_research/2019-5/
• https://support.f5.com/csp/article/K12671141
• https://usn.ubuntu.com/3930-1/
• https://usn.ubuntu.com/3930-2/
• https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.21
• https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.20.8
• https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/?id=ba59fb0273076637f0add4311faa990a5eec27c0
• https://secuniaresearch.flexerasoftware.com/secunia_research/2019-5/
• https://support.f5.com/csp/article/K12671141

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