CVE-2019-11477: Integer overflow in TCP_SKB_CB(skb)->tcp_gso_segs

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 98.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-06-19 · updated 2026-06-17
Weakness: CWE-190

Description

Jonathan Looney discovered that the TCP_SKB_CB(skb)->tcp_gso_segs value was subject to an integer overflow in the Linux kernel when handling TCP Selective Acknowledgments (SACKs). A remote attacker could use this to cause a denial of service. This has been fixed in stable kernel releases 4.4.182, 4.9.182, 4.14.127, 4.19.52, 5.1.11, and is fixed in commit 3b4929f65b0d8249f19a50245cd88ed1a2f78cff.

Affected products

Canonical Ubuntu Linux: 12.04, 14.04, 16.04, 18.04, 18.10, 19.04
F5 BIG-IP APM: from 11.5.2 through 11.6.4; from 12.1.0 through 12.1.4; from 13.1.0 through 13.1.1; from 14.0.0 through 14.1.0; 15.0.0
BIG-IP: from 11.5.2 through 11.6.4; from 12.1.0 through 12.1.4; from 13.1.0 through 13.1.1; from 14.0.0 through 14.1.0; 15.0.0
F5 Big-Ip Analytics: from 11.5.2 through 11.6.4; from 12.1.0 through 12.1.4; from 13.1.0 through 13.1.1; from 14.0.0 through 14.1.0; 15.0.0
F5 Networks, Inc. BIG-IP (AAM): from 11.5.2 through 11.6.4; from 12.1.0 through 12.1.4; from 13.1.0 through 13.1.1; from 14.0.0 through 14.1.0; 15.0.0
BIG-IP ASM: from 11.5.2 through 11.6.4; from 12.1.0 through 12.1.4; from 13.1.0 through 13.1.1; from 14.0.0 through 14.1.0; 15.0.0
F5 BIG-IP DNS: from 11.5.2 through 11.6.4; from 12.1.0 through 12.1.4; from 13.1.0 through 13.1.1; from 14.0.0 through 14.1.0; 15.0.0
F5 Big-Ip Edge Gateway: from 11.5.2 through 11.6.4; from 12.1.0 through 12.1.4; from 13.1.0 through 13.1.1; from 14.0.0 through 14.1.0; 15.0.0
F5 Big-Ip Fraud Protection Service: from 11.5.2 through 11.6.4; from 12.1.0 through 12.1.4; from 13.1.0 through 13.1.1; from 14.0.0 through 14.1.0; 15.0.0
F5 Big-Ip Global Traffic Manager: from 11.5.2 through 11.6.4; from 12.1.0 through 12.1.4; from 13.1.0 through 13.1.1; from 14.0.0 through 14.1.0; 15.0.0
F5 Big-Ip Link Controller: from 11.5.2 through 11.6.4; from 12.1.0 through 12.1.4; from 13.1.0 through 13.1.1; from 14.0.0 through 14.1.0; 15.0.0
F5 BIG-IP (LTM): from 11.5.2 through 11.6.4; from 12.1.0 through 12.1.4; from 13.1.0 through 13.1.1; from 14.0.0 through 14.1.0; 15.0.0
F5 Networks, Inc. BIG-IP (PEM): from 11.5.2 through 11.6.4; from 12.1.0 through 12.1.4; from 13.1.0 through 13.1.1; from 14.0.0 through 14.1.0; 15.0.0
F5 Big-Ip Webaccelerator: from 11.5.2 through 11.6.4; from 12.1.0 through 12.1.4; from 13.1.0 through 13.1.1; from 14.0.0 through 14.1.0; 15.0.0
F5 Traffix SDC: from 5.0.0 through 5.1.0
Ivanti Connect Secure (Pulse Secure): all versions
Linux kernel: from 2.6.29 before 3.16.69; from 3.17 before 4.4.182; from 4.5 before 4.9.182; from 4.10 before 4.14.127; from 4.15 before 4.19.52; from 4.20 before 5.1.11 — fixed in 3.16.69, 4.14.127, 4.19.52, 4.4.182, 4.9.182, 5.1.11
Pulsesecure Pulse Policy Secure: all versions
Pulsesecure Pulse Secure Virtual Application Delivery Controller: all versions
Red Hat Enterprise Linux: 5.0, 6.0, 7.0, 8.0
RedHat Enterprise Linux Atomic Host: all versions
RedHat Enterprise Linux Aus: 6.5, 6.6
RedHat Enterprise Linux Eus: 7.4, 7.5
RedHat Enterprise Mrg: 2.0

How to fix

Upgrade to a fixed version: Linux kernel 3.16.69, 4.14.127, 4.19.52, 4.4.182. Check the vendor advisory for mitigations.

References

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