Resource exhaustion in F5 Big-Ip Access Policy Manager
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 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.
EPSS: 0.917 (99.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
Affected products
- F5 Big-ip_access_policy_manager
- F5 Big-ip_advanced_firewall_manager
- F5 Big-ip_analytics
- F5 Big-ip_application_acceleration_manager
- F5 Big-ip_application_security_manager
- F5 Big-ip_domain_name_system
- F5 Big-ip_edge_gateway
- F5 Big-ip_fraud_protection_service
- F5 Big-ip_global_traffic_manager
- F5 Big-ip_link_controller
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security@ubuntu.com (VDB Entry, Third Party Advisory, vdb-entry, x_refsource_BID)
- security@ubuntu.com (US Government Resource, x_refsource_CERT-VN, Third Party Advisory, third-party-advisory)
- security@ubuntu.com (x_refsource_REDHAT, vendor-advisory, Third Party Advisory)
- security@ubuntu.com (x_refsource_REDHAT, vendor-advisory, Third Party Advisory)
- security@ubuntu.com (mailing-list, x_refsource_MLIST, Mailing List, Third Party Advisory)
- security@ubuntu.com (x_refsource_UBUNTU, vendor-advisory, Third Party Advisory)
- security@ubuntu.com (mailing-list, x_refsource_MLIST, Mailing List, Third Party Advisory)
- security@ubuntu.com (mailing-list, x_refsource_MLIST, Mailing List, Third Party Advisory)
- security@ubuntu.com (x_refsource_REDHAT, vendor-advisory, Third Party Advisory)
- security@ubuntu.com (x_refsource_UBUNTU, vendor-advisory, Third Party Advisory)
Frequently asked questions
- What is CVE-2019-11479?
- CVE-2019-11479 is a high-severity vulnerability in F5 Big-Ip Access Policy Manager, classified under Asymmetric Resource Consumption (Amplification). CVSS score: 7.5/10. Published 2019-06-19.
- How severe is CVE-2019-11479?
- High severity. CVSS v3 base score is 7.5 out of 10.
- Is CVE-2019-11479 known to be exploited?
- 7 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.