CVE-2016-6197

fs/overlayfs/dir.c in the OverlayFS filesystem implementation in the Linux kernel before 4.6 does not properly verify the upper dentry before proceeding with unlink and rename system-call processing, which allows local users to cause a denial of service (system crash) via a rename system call that specifies a self-hardlink.

Published: 2016-08-06 Last update: 2026-05-06 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2016-6197 is rated Low Risk (28.1/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.06%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2016-6197

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-02-20 0.04% 0.06% +0.02%
2 2025-03-30 0.19% 0.04% -0.15%
3 2025-03-29 — 0.19% —

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2016-6197

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.5 3.0 MEDIUM
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 3.6 [email protected]
4.9 2.0 MEDIUM
AV:L/AC:L/Au:N/C:N/I:N/A:C Click to expand
Access vector (AV:L)
Requires local access to the target system.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:C)
Complete availability impact.
 3.9 6.9 [email protected]

Weakness enumeration for CVE-2016-6197

OS Trackers for CVE-2016-6197

vendor priority summary link
debian not yet assigned CVE-2016-6197 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2016-6197
redhat medium — https://access.redhat.com/security/cve/CVE-2016-6197
suse medium CVE-2016-6197 severity moderate: SUSE including 36 source package names (kernel-default, kernel-default-4.4.21-69.1, …), 333 product×package rows across 79 product lines (SUSE CaaS Platform 4.0, SUSE CaaS Platform 4.5, … (79 product lines)): Known Not Affected 290, Fixed 43. https://www.suse.com/security/cve/CVE-2016-6197/
ubuntu low CVE-2016-6197 low priority: Ubuntu including 104 source packages (linux, linux-armadaxp, …), 1064 status rows across 17 suites (artful, bionic, cosmic, disco, eoan, focal, jammy, noble, oracular, plucky, precise, trusty, upstream, wily, xenial, yakkety, zesty): DNE 739, not-affected 180, released 108, ignored 37. https://ubuntu.com/security/CVE-2016-6197

Affected software / configurations for CVE-2016-6197

Vendor Product Version Raw CPE
oracle linux 6 cpe:2.3:o:oracle:linux:6:*:*:*:*:*:*:*
linux linux_kernel <= 4.5.7 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
oracle vm_server 3.4 cpe:2.3:o:oracle:vm_server:3.4:*:*:*:*:*:*:*

References for CVE-2016-6197

URL Tags
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=11f3710417d026ea2f4fcf362d866342c5274185 Issue Tracking Patch
http://rhn.redhat.com/errata/RHSA-2016-1847.html
http://rhn.redhat.com/errata/RHSA-2016-1875.html
http://www.openwall.com/lists/oss-security/2016/07/11/8 Mailing List Third Party Advisory
http://www.oracle.com/technetwork/topics/security/linuxbulletinjul2016-3090544.html Third Party Advisory
http://www.oracle.com/technetwork/topics/security/ovmbulletinjul2016-3090546.html Vendor Advisory
http://www.securityfocus.com/bid/91709
http://www.securitytracker.com/id/1036273
http://www.ubuntu.com/usn/USN-3070-1
http://www.ubuntu.com/usn/USN-3070-2
http://www.ubuntu.com/usn/USN-3070-3
http://www.ubuntu.com/usn/USN-3070-4
https://bugzilla.redhat.com/show_bug.cgi?id=1355650 Issue Tracking
https://github.com/torvalds/linux/commit/11f3710417d026ea2f4fcf362d866342c5274185 Issue Tracking Patch
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