7.8

CVE-2025-38704: rcu/nocb: Fix possible invalid rdp's->nocb_cb_kthread pointer access

Modified
AliasesUBUNTU-CVE-2025-38704DEBIAN-CVE-2025-38704
Published 04-09-2025Last modified 15-10-2026

Vulnerability summary

CVE-2025-38704 is a high (CVSS 7.8) vulnerability in linux. EPSS estimates a 0.18% chance of exploitation in the next 30 days, higher than 7.8% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 7.8, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
7.8/10
010
High · v3.1 (NVD)
EPSS score
0.18%
0%100%
Low · +0.01 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 28 · Related 28
OPENSUSE-SU-2026:20145-1SUSE-SU-2026:20207-1SUSE-SU-2026:20220-1SUSE-SU-2026:20228-1SUSE-SU-2026:20564-1SUSE-SU-2026:24181-1

Timeline

  1. 04-09-2025
    PublishedVulnerability first disclosed.
  2. 15-10-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: rcu/nocb: Fix possible invalid rdp's->nocb_cb_kthread pointer access In the preparation stage of CPU online, if the corresponding the rdp's->nocb_cb_kthread does not exist, will be created, there is a situation where the rdp's rcuop kthreads creation fails, and then de-offload this CPU's rdp, does not assign this CPU's rdp->nocb_cb_kthread pointer, but this rdp's->nocb_gp_rdp and rdp's->rdp_gp->nocb_gp_kthread is still valid. This will cause the subsequent re-offload operation of this offline CPU, which will pass the conditional check and the kthread_unpark() will access invalid rdp's->nocb_cb_kthread pointer. This commit therefore use rdp's->nocb_gp_kthread instead of rdp_gp's->nocb_gp_kthread for safety check.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.18%

Chance of exploitation in the next 30 days

Percentile

8%

Versus all other CVEs

30-day change

Increase +0.01 pp

From 0.17% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Version check

Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Ubuntu122 products
  • linux< 6.8.0-100.100
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-aws< 6.8.0-1046.49
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux2 products
  • linux≥ 3a5761dc025da47960755ac64d9fbf1c32e8cd80, < b097ae798298885695c339d390b48b4e39619fa7 | ≥ 3a5761dc025da47960755ac64d9fbf1c32e8cd80, < 3da45ec1e485a1a5ad31fe9ddd467c7ee5ae4ef9 | ≥ 3a5761dc025da47960755ac64d9fbf1c32e8cd80, < cce3d027227c69e85896af9fbc6fa9af5c68f067 | ≥ 3a5761dc025da47960755ac64d9fbf1c32e8cd80, < 1c951683a720b17c9ecaad1932bc95b29044611f | ≥ 3a5761dc025da47960755ac64d9fbf1c32e8cd80, < 9b5ec8e6b31755288a07b3abeeab8cd38e9d3c9d | ≥ 3a5761dc025da47960755ac64d9fbf1c32e8cd80, < 1bba3900ca18bdae28d1b9fa10f16a8f8cb2ada1 | 6.0
  • linux_kernel< 6.12.43 | ≥ 6.13, < 6.15.11 | ≥ 6.16, < 6.16.2
Debian1 product
  • linux< 6.1.170-1 | < 6.12.43-1 | < 6.16.3-1

3 vendors · 125 products

References

31 links
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