CVE-2016-6828: linux linux_kernel Use After Free
Vulnerability summary
CVE-2016-6828 is a medium (CVSS 5.5) Use After Free vulnerability in linux linux_kernel. EPSS estimates a 1.18% chance of exploitation in the next 30 days, higher than 67.7% of scored vulnerabilities. 2 public exploits are recorded.
Not severe (CVSS 5.5, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 21 · Related 13Timeline
- 16-10-2016PublishedVulnerability first disclosed.
- 06-08-2024Last modifiedVulnerability information updated.
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 metrics
4 scores · 3 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated5.5MediumCVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated5.5MediumCVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
1.18%
Chance of exploitation in the next 30 days
Percentile
68%
Versus all other CVEs
30-day change
No change 0.00 pp
From 1.18% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
2 foundExploit Reference (openwall.com)
Maturity: unknown
Linux Kernel - TCP Related Read Use-After-Free
Maturity: poc
Weaknesses
CWE · root causeAffected systems
Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu5 products
- linux< 3.13.0-98.145 | < 4.4.0-42.62
- linux-lts-vivid< 3.19.0-71.79~14.04.1
- linux-lts-xenial< 4.4.0-42.62~14.04.1
- linux-raspi2< 4.4.0-1027.33
- linux-snapdragon< 4.4.0-1030.33
Debian1 product
- linux< 4.7.2-1
Linux1 product
- linux_kernel≤ 4.7.4
3 vendors · 7 products
References
24 links- github.com/torvalds/linux/commit/bb1fceca22492109be12640d49f5ea5a544c6bb4X Refsource CONFIRMIssue TrackingPatch
- www.openwall.com/lists/oss-security/2016/08/15/1Mailing ListX Refsource MLISTExploitThird Party Advisory
- source.android.com/security/bulletin/2016-11-01.htmlX Refsource CONFIRM
Show all 24 references
- www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.7.5X Refsource CONFIRMRelease NotesThird Party Advisory
