CVE-2019-11478

SACK can cause extensive memory use via fragmented resend queue

Description

Jonathan Looney discovered that the TCP retransmission queue implementation in tcp_fragment in the Linux kernel could be fragmented when handling certain TCP Selective Acknowledgment (SACK) sequences. 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 f070ef2ac66716357066b683fb0baf55f8191a2e.

Categories

5.3
CVSS
Severity: Medium
CVSS 3.0 •
CVSS 2.0 •
EPSS 27.96% Top 5%
Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory kernel.org
Affected: Linux Linux kernel
Published at:
Updated at:

References

Link Tags
https://www.kb.cert.org/vuls/id/905115 third party advisory
https://access.redhat.com/errata/RHSA-2019:1594 vendor advisory
https://access.redhat.com/errata/RHSA-2019:1602 vendor advisory
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 mailing list
https://access.redhat.com/errata/RHSA-2019:1699 vendor advisory
https://seclists.org/bugtraq/2019/Jul/30 mailing list
http://www.openwall.com/lists/oss-security/2019/10/24/1 mailing list
http://www.openwall.com/lists/oss-security/2019/10/29/3 mailing list
https://www.oracle.com/security-alerts/cpujan2020.html
https://www.oracle.com/security-alerts/cpuoct2020.html
https://github.com/Netflix/security-bulletins/blob/master/advisories/third-party/2019-001.md third party advisory patch
https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/SACKPanic third party advisory mitigation
https://access.redhat.com/security/vulnerabilities/tcpsack third party advisory
http://packetstormsecurity.com/files/153346/Kernel-Live-Patch-Security-Notice-LSN-0052-1.html vdb entry third party advisory
https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44193 third party advisory
https://www.synology.com/security/advisory/Synology_SA_19_28
https://security.netapp.com/advisory/ntap-20190625-0001/
https://kc.mcafee.com/corporate/index?page=content&id=SB10287
http://www.vmware.com/security/advisories/VMSA-2019-0010.html
https://cert-portal.siemens.com/productcert/pdf/ssa-462066.pdf
https://www.us-cert.gov/ics/advisories/icsa-19-253-03
http://packetstormsecurity.com/files/154951/Kernel-Live-Patch-Security-Notice-LSN-0058-1.html
http://www.arubanetworks.com/assets/alert/ARUBA-PSA-2020-010.txt
https://git.kernel.org/pub/scm/linux/kernel/git/davem/net.git/commit/?id=f070ef2ac66716357066b683fb0baf55f8191a2e mailing list patch vendor advisory
https://support.f5.com/csp/article/K26618426 third party advisory
https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2019-0007
http://packetstormsecurity.com/files/154408/Kernel-Live-Patch-Security-Notice-LSN-0055-1.html

Frequently Asked Questions

What is the severity of CVE-2019-11478?
CVE-2019-11478 has been scored as a medium severity vulnerability.
How to fix CVE-2019-11478?
To fix CVE-2019-11478, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2019-11478 being actively exploited in the wild?
It is possible that CVE-2019-11478 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~28% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2019-11478?
CVE-2019-11478 affects Linux Linux kernel.
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