CVE-2016-6828
The tcp_check_send_head function in include/net/tcp.h in the Linux kernel before 4.7.5 does not properly maintain certain SACK state after a failed data copy, which allows local users to cause a denial of service (tcp_xmit_retransmit_queue…
Does this matter?
A public exploit is published in Exploit-DB, so the technical barrier is gone even though the severity is medium and EPSS is 1.2%. Treat it as high on anything reachable from the internet.
Description
The tcp_check_send_head function in include/net/tcp.h in the Linux kernel before 4.7.5 does not properly maintain certain SACK state after a failed data copy, which allows local users to cause a denial of service (tcp_xmit_retransmit_queue use-after-free and system crash) via a crafted SACK option.
- CVSS 3.0
- 5.5 MEDIUMCVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 1.18% probability · 68th percentile
- Public exploits
- 1 in Exploit-DB · first 18 August 2016
- CISA KEV
- Not listed
- Weakness
- CWE-416
- Affected
- linux/linux kernel
- Source
- secalert@redhat.com
EPSS 1.2% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
Public exploits (1)
Entries in Exploit-DB that cite this CVE. Links go to the Exploit-DB page and to the file in the public repository; nothing is hosted here. A verified tick means the Exploit-DB team confirmed the exploit works against the stated version.
References
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=bb1fceca22492109be12640d49f5ea5a544c6bb4Issue Tracking, Patch
- http://rhn.redhat.com/errata/RHSA-2017-0036.html
- http://rhn.redhat.com/errata/RHSA-2017-0086.html
- http://rhn.redhat.com/errata/RHSA-2017-0091.html
- http://rhn.redhat.com/errata/RHSA-2017-0113.html
- http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.7.5Release Notes, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2016/08/15/1Exploit, Third Party Advisory
- http://www.securityfocus.com/bid/92452
- https://bugzilla.redhat.com/show_bug.cgi?id=1367091Issue Tracking, Third Party Advisory
- https://github.com/torvalds/linux/commit/bb1fceca22492109be12640d49f5ea5a544c6bb4Issue Tracking, Patch
- https://marcograss.github.io/security/linux/2016/08/18/cve-2016-6828-linux-kernel-tcp-uaf.html
- https://source.android.com/security/bulletin/2016-11-01.html
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=bb1fceca22492109be12640d49f5ea5a544c6bb4Issue Tracking, Patch
- http://rhn.redhat.com/errata/RHSA-2017-0036.html
- http://rhn.redhat.com/errata/RHSA-2017-0086.html
- http://rhn.redhat.com/errata/RHSA-2017-0091.html
- http://rhn.redhat.com/errata/RHSA-2017-0113.html
- http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.7.5Release Notes, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2016/08/15/1Exploit, Third Party Advisory
- http://www.securityfocus.com/bid/92452
- https://bugzilla.redhat.com/show_bug.cgi?id=1367091Issue Tracking, Third Party Advisory
- https://github.com/torvalds/linux/commit/bb1fceca22492109be12640d49f5ea5a544c6bb4Issue Tracking, Patch
- https://marcograss.github.io/security/linux/2016/08/18/cve-2016-6828-linux-kernel-tcp-uaf.html
- https://source.android.com/security/bulletin/2016-11-01.html
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.