CVE-2019-11479

MEDIUM

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.

References

http://www.openwall.com/lists/oss-security/2019/06/28/2

http://www.openwall.com/lists/oss-security/2019/07/06/3

http://www.openwall.com/lists/oss-security/2019/07/06/4

http://www.securityfocus.com/bid/108818

https://access.redhat.com/errata/RHSA-2019:1594

https://access.redhat.com/errata/RHSA-2019:1602

https://access.redhat.com/errata/RHSA-2019:1699

https://access.redhat.com/security/vulnerabilities/tcpsack

https://cert-portal.siemens.com/productcert/pdf/ssa-462066.pdf

https://git.kernel.org/pub/scm/linux/kernel/git/davem/net.git/commit/?id=5f3e2bf008c2221478101ee72f5cb4654b9fc363

https://git.kernel.org/pub/scm/linux/kernel/git/davem/net.git/commit/?id=967c05aee439e6e5d7d805e195b3a20ef5c433d6

https://github.com/Netflix/security-bulletins/blob/master/advisories/third-party/2019-001.md

https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44193

https://kc.mcafee.com/corporate/index?page=content&id=SB10287

https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2019-0008

https://security.netapp.com/advisory/ntap-20190625-0001/

https://support.f5.com/csp/article/K35421172

https://support.f5.com/csp/article/K35421172?utm_source=f5support&utm_medium=RSS

https://usn.ubuntu.com/4041-1/

https://usn.ubuntu.com/4041-2/

https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/SACKPanic

https://www.kb.cert.org/vuls/id/905115

https://www.synology.com/security/advisory/Synology_SA_19_28

https://www.us-cert.gov/ics/advisories/icsa-19-253-03

Details

Source: MITRE

Published: 2019-06-19

Updated: 2019-06-20

Type: CWE-400

Risk Information

CVSS v2.0

Base Score: 5

Vector: AV:N/AC:L/Au:N/C:N/I:N/A:P

Impact Score: 2.9

Exploitability Score: 10

Severity: MEDIUM

CVSS v3.0

Base Score: 7.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Impact Score: 3.6

Exploitability Score: 3.9

Severity: HIGH