High severity · published Jun 19, 2019
CVE-2019-11479
Jonathan Looney discovered that the Linux kernel default MSS is hard-coded to 48 bytes
7.5
CVSS
91.7%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)91.7% · higher than 100% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
4.4 before 4.4.182; 4.9 before 4.9.182; 4.14 before 4.14.127; 4.19 before 4.19.52; 5.1 before 5.1.11 · source: NVD
BA
Big-ip Access Policy Manager · F5
11.5.2 before 11.6.5.1; 12.1.0 before 12.1.5.1; 13.1.0 before 13.1.3.2; 14.0.0 before 14.0.1.1; 14.1.2 before 14.1.2.1; 15.0.0 before 15.0.1.1 · source: NVD
BA
Big-ip Advanced Firewall Manager · F5
11.5.2 before 11.6.5.1; 12.1.0 before 12.1.5.1; 13.1.0 before 13.1.3.2; 14.0.0 before 14.0.1.1; 14.1.2 before 14.1.2.1; 15.0.0 before 15.0.1.1 · source: NVD
BA
Big-ip Analytics · F5
11.5.2 before 11.6.5.1; 12.1.0 before 12.1.5.1; 13.1.0 before 13.1.3.2; 14.0.0 before 14.0.1.1; 14.1.2 before 14.1.2.1; 15.0.0 before 15.0.1.1 · source: NVD
BA
Big-ip Application Acceleration Manager · F5
11.5.2 before 11.6.5.1; 12.1.0 before 12.1.5.1; 13.1.0 before 13.1.3.2; 14.0.0 before 14.0.1.1; 14.1.2 before 14.1.2.1; 15.0.0 before 15.0.1.1 · source: NVD
BA
Big-ip Application Security Manager · F5
11.5.2 before 11.6.5.1; 12.1.0 before 12.1.5.1; 13.1.0 before 13.1.3.2; 14.0.0 before 14.0.1.1; 14.1.2 before 14.1.2.1; 15.0.0 before 15.0.1.1 · source: NVD
BD
Big-ip Domain Name System · F5
11.5.2 before 11.6.5.1; 12.1.0 before 12.1.5.1; 13.1.0 before 13.1.3.2; 14.0.0 before 14.0.1.1; 14.1.2 before 14.1.2.1; 15.0.0 before 15.0.1.1 · source: NVD
BE
Big-ip Edge Gateway · F5
11.5.2 before 11.6.5.1; 12.1.0 before 12.1.5.1; 13.1.0 before 13.1.3.2; 14.0.0 before 14.0.1.1; 14.1.2 before 14.1.2.1; 15.0.0 before 15.0.1.1 · source: NVD
BF
Big-ip Fraud Protection Service · F5
11.5.2 before 11.6.5.1; 12.1.0 before 12.1.5.1; 13.1.0 before 13.1.3.2; 14.0.0 before 14.0.1.1; 14.1.2 before 14.1.2.1; 15.0.0 before 15.0.1.1 · source: NVD
BG
Big-ip Global Traffic Manager · F5
11.5.2 before 11.6.5.1; 12.1.0 before 12.1.5.1; 13.1.0 before 13.1.3.2; 14.0.0 before 14.0.1.1; 14.1.2 before 14.1.2.1; 15.0.0 before 15.0.1.1 · source: NVD
BL
Big-ip Link Controller · F5
11.5.2 before 11.6.5.1; 12.1.0 before 12.1.5.1; 13.1.0 before 13.1.3.2; 14.0.0 before 14.0.1.1; 14.1.2 before 14.1.2.1; 15.0.0 before 15.0.1.1 · source: NVD
BL
Big-ip Local Traffic Manager · F5
11.5.2 before 11.6.5.1; 12.1.0 before 12.1.5.1; 13.1.0 before 13.1.3.2; 14.0.0 before 14.0.1.1; 14.1.2 before 14.1.2.1; 15.0.0 before 15.0.1.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2019-11479
CVE.org
https://www.cve.org/CVERecord?id=CVE-2019-11479
Third Party Advisory
http://www.arubanetworks.com/assets/alert/ARUBA-PSA-2020-010.txt
Mailing List
http://www.openwall.com/lists/oss-security/2019/06/28/2
Mailing List
http://www.openwall.com/lists/oss-security/2019/07/06/3
Mailing List
http://www.openwall.com/lists/oss-security/2019/07/06/4
Third Party Advisory
http://www.securityfocus.com/bid/108818
Third Party Advisory
https://access.redhat.com/errata/RHSA-2019:1594
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