SYSTEM - CVE-2017-18017 Subscribe to Security Advisories

Sunday, August 19, 2018
Sunday, August 19, 2018

In January 2018, a vulnerability was published affecting the operating system in ACOS 3.x and 4.x. This vulnerability is addressed in this document.

Item # Vulnerability ID Score Source Score Summary
1 CVE-2017-18017 CVSS 3.0 9.8 Critical kernel: netfilter: User-after-free in tcpmss_mangle_packet() in xt_TCPMSS.c

Affected Releases

The table below indicates releases of ACOS exposed to these vulnerabilities and ACOS releases that address them. ACOS release families not indicated below are unaffected by these vulnerabilities.

Customers using affected ACOS releases can overcome vulnerability exposures by updating to the indicated resolved release. If the table does not list a corresponding resolved or unaffected release, then no ACOS release update is currently available.

Releases AffectedReleases Resolved or Unaffected

4.1.2 – 4.1.2-P4


4.1.1 – 4.1.1-P8


4.1.0 – 4.1.0-P11


3.2.2 – 3.2.2-P4


Workarounds and Mitigations 


Software Updates 

Software updates that address these vulnerabilities are or will be published at the following URL:

Vulnerability Details

The following table shares brief descriptions of the vulnerabilities addressed in this document.

Vulnerability IDVulnerability Description

The tcpmss_mangle_packet function in net/netfilter/xt_TCPMSS.c in the Linux kernel before 4.11, and 4.9.x before 4.9.36, allows remote attackers to cause a denial of service (use-after-free and memory corruption) or possibly have unspecified other impact by leveraging the presence of xt_TCPMSS in an iptables action.



Modification History 
August 19, 2018

Initial Publication

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