Threats / Linux / CVE-2023-0386
CVE-2023-0386
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-06-22
Linux Kernel vulnerability
Linux Kernel OverlayFS contains an improper ownership management vulnerability allowing local privilege escalation through setuid file capability abuse across mount boundaries.
Verdict
Today item — known-exploited.
A local attacker can exploit uid mapping flaws in OverlayFS to copy capable setuid files from nosuid mounts, gaining unauthorized elevated privileges. This vulnerability has been actively exploited in the wild.
01
Is it exploitable?
— the evidence, ranked above the scoreExploit available
Fully weaponized — public exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported exploitation
2 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2025-06-17).
Probability (EPSS)
EPSS 0.0788 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Linux, Kernel. Confirm exact fixed builds in the vendor advisory.
Weakness (CWE)
Mapped to CWE-282 CWE-282.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
WeaknessCWE-282 · CWE-282
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution not established
No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.
03
Why it matters
— the attack path, told twice: adversary, then board1
Front door — unauthenticated access narrative 1
Attacker
I identify a capable setuid file on a nosuid mount that I cannot normally execute with elevated privileges.
Business
System maintains restrictive mount policies to prevent privilege escalation vectors.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I exploit OverlayFS uid mapping logic to copy this file to another mount where ownership rules are misapplied.
Business
Kernel's overlay filesystem fails to properly validate capability inheritance across mount contexts.
3
Lateral reach — past segmentation narrative 3
Attacker
I execute the copied file and gain setuid execution with its embedded capabilities, escalating to root or another privileged user.
Business
Attacker achieves local privilege escalation, compromising system integrity and confidentiality.
04
What to do
— defensible action- Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05