CVE-2026-52791Public exploit

Privilege retention via uncleared SUID and SGID bits

Published Jul 29, 2026 · Updated Jul 29, 2026

Incorrect privilege assignment in Containers fuse-overlayfs before 1.17 allows local users to preserve SUID or SGID bits by truncating files. The C release-1.x open and setattr truncation paths copy up writable lower-layer files without clearing S_ISUID or S_ISGID, leaving upper-layer mode 4777. Reachability requires a local low-privileged process with write access through a fuse-overlayfs merged mount; the proven result is retained privilege bits, not host root or container escape.

CVSS severity2.0
Low
EPSS probability0.10%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Incorrect privilege assignment in Containers fuse-overlayfs before 1.17 allows local users to preserve SUID or SGID bits by truncating files. The C release-1.x open and setattr truncation paths copy up writable lower-layer files without clearing S_ISUID or S_ISGID, leaving upper-layer mode 4777. Reachability requires a local low-privileged process with write access through a fuse-overlayfs merged mount; the proven result is retained privilege bits, not host root or container escape.

The record

CVE
CVE-2026-52791
Published
Jul 29, 2026
Updated
Jul 29, 2026
Vendor
Containers
Product
fuse-overlayfs
Classifications
CWE-266, T1548.001
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 29, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 29, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 1.17

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Containers · fuse-overlayfsversion=< 1.17

Published CVSS scores

2.0GitHubCVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-266Incorrect Privilege Assignment
T1548.001Setuid and Setgid

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo