CVE-2026-78409

highpriority · track · 28EPSS 0.002 · 9 %ileDEUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.19% (9th) EPSS
CVSS 7 · high
Is it mine?
5 products
Check your exposure
Who says so?
1 sources
cert_bund

EPSS · scored 2026-10-28

The X-mount.subdir option uses a detached-tree fast path on Linux 6.15 and later and passes the configured subdirectory to open_tree() with AT_SYMLINK_NOFOLLOW. That flag does not stop intermediate symlink traversal or keep resolution inside the newly mounted filesystem. A local unprivileged user with an fstab-authorized X-mount.subdir entry can attach a host path at the intended mountpoint.

01

cvss

Technical severity, 0–10. One row per scoring source.

7.0
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.4–7

v3.17highCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:Hprimary · secalert@redhat.com USexploitability 1 · impact 5.9
v3.16.4mediumCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: poc · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-59US
04

affected products (5)

Products and version ranges known to be affected.

05

advisories (1)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2026-3160util-linux: Mehrere SchwachstellenDeutsch2026-09-02csaf · cert_bundDE

    Ein lokaler Angreifer kann mehrere Schwachstellen in util-linux ausnutzen, um Sicherheitsvorkehrungen zu umgehen und um Administrative Aktionen an Zugriffsrechten vollziehen.

06

sources

Which sources assert this record, and when.

cert_bundNVDCVE.orgMITRE
published 2026-09-02modified 2026-10-21
07

references (4) nvd

External citations — patches, advisories, analysis.

scry

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