HIGH · 7.5

CVE-2019-11479

Jonathan Looney discovered that the Linux kernel default MSS is hard-coded to 48 bytes. This allows a remote peer to fragment TCP resend queues significantly more than if a larger MSS were enforced. A...

Vulnerability Description

Jonathan Looney discovered that the Linux kernel default MSS is hard-coded to 48 bytes. This allows a remote peer to fragment TCP resend queues significantly more than if a larger MSS were enforced. 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 commits 967c05aee439e6e5d7d805e195b3a20ef5c433d6 and 5f3e2bf008c2221478101ee72f5cb4654b9fc363.

CVSS Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH

Affected Products

VendorProductVersions
LinuxLinux Kernel>= 4.4, < 4.4.182
F5Big-Ip Advanced Firewall Manager>= 11.5.2, < 11.6.5.1
F5Big-Ip Access Policy Manager>= 11.5.2, < 11.6.5.1
F5Big-Ip Application Acceleration Manager>= 11.5.2, < 11.6.5.1
F5Big-Ip Link Controller>= 11.5.2, < 11.6.5.1
F5Big-Ip Policy Enforcement Manager>= 11.5.2, < 11.6.5.1
F5Big-Ip Webaccelerator>= 11.5.2, < 11.6.5.1
F5Big-Ip Application Security Manager>= 11.5.2, < 11.6.5.1
F5Big-Ip Local Traffic Manager>= 11.5.2, < 11.6.5.1
F5Big-Ip Fraud Protection Service>= 11.5.2, < 11.6.5.1
F5Big-Ip Global Traffic Manager>= 11.5.2, < 11.6.5.1
F5Big-Ip Analytics>= 11.5.2, < 11.6.5.1
F5Big-Ip Edge Gateway>= 11.5.2, < 11.6.5.1
F5Big-Ip Domain Name System>= 11.5.2, < 11.6.5.1
CanonicalUbuntu Linux14.04
RedhatEnterprise Linux7.0
F5Big-Iq Centralized Management>= 5.1.0, <= 5.4.0
F5Enterprise Manager3.1.1
F5Iworkflow2.3.0
F5Traffix Signaling Delivery Controller>= 5.0.0, <= 5.1.0

Related Weaknesses (CWE)

References

FAQ

What is CVE-2019-11479?

CVE-2019-11479 is a vulnerability with a CVSS score of 7.5 (HIGH). Jonathan Looney discovered that the Linux kernel default MSS is hard-coded to 48 bytes. This allows a remote peer to fragment TCP resend queues significantly more than if a larger MSS were enforced. A...

How severe is CVE-2019-11479?

CVE-2019-11479 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2019-11479?

Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel, F5 Big-Ip Advanced Firewall Manager, F5 Big-Ip Access Policy Manager, F5 Big-Ip Application Acceleration Manager, F5 Big-Ip Link Controller.