CVE-2026-68166: linux

CVSS: UnknownReceived
AliasesUBUNTU-CVE-2026-68166DEBIAN-CVE-2026-68166
Published 10-08-2026Last modified 23-08-2026
Open JSON

Vulnerability summary

CVE-2026-68166 is a vulnerability in linux with no CVSS score yet. EPSS estimates a 0.21% chance of exploitation in the next 30 days, higher than 9.9% of scored vulnerabilities.

Overall risk
0/100
0100
Minimal · default modelHow is this calculated?
CVSS score
Not scored
010
No CVSS score recorded
EPSS score
0.21%
0%100%
Low · +0.01 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 23 · Related 17
MGASA-2026-0336MGASA-2026-0337OPENSUSE-SU-2026:21910-1RHSA-2026:61887RHSA-2026:63129RHSA-2026:67720

Timeline

  1. 10-08-2026
    PublishedVulnerability first disclosed.
  2. 23-08-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: userfaultfd: prevent registration of special VMAs Vova Tokarev says: userfaultfd allows registration on shadow stack VMAs. With userfaultfd access, you can register on the shadow stack, discard a page ... and inject a page with chosen return addresses via UFFDIO_COPY. Update vma_can_userfault() to reject VM_SHADOW_STACK. While on it, also reject VM_SPECIAL so that if a driver would implement vm_uffd_ops, it wouldn't be possible to register special VMAs with userfaultfd. Since VM_SPECIAL includes VM_DONTEXPAND which is set but hugetlb, exclude hugetlb VMAs from the check for VM_SPECIAL.

CVSS metrics

Risk metrics not yet published.

EPSS trend

Probability

0.21%

Chance of exploitation in the next 30 days

Percentile

10%

Versus all other CVEs

30-day change

+0.01 pp

From 0.20% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.21%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Ubuntu142 products
  • linuxAll versions (No fix recorded) | < 7.0.0-38.38
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 7.0.0-1014.14
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian2 products
  • linux< 6.12.105-1 | < 7.1.6-1
  • linux-6.12< 6.12.107-1~deb12u1
Linux1 product
  • linux≥ 54007f818206dc27309ca423df4c87dd160a7208, < d974b4b786214883bd8e56bda10b454c80fd6205 | ≥ 54007f818206dc27309ca423df4c87dd160a7208, < 495a28d5a100be1b232633f4c2dcc42ba10b3796 | ≥ 54007f818206dc27309ca423df4c87dd160a7208, < 165613191ad9d034bf17c00e3a142f9561597ec5 | ≥ 54007f818206dc27309ca423df4c87dd160a7208, < 0c26202b157f1efc3cd2f26f5c30f59b508a6a5d | ≥ 54007f818206dc27309ca423df4c87dd160a7208, < 3c58f641e813c3c71039f8fd4d4e2a3aab713288 | 6.6

3 vendors · 145 products

References

15 links
Show all 15 references