5.5

CVE-2022-49090: arch/arm64: Fix topology initialization for core scheduling

Analyzed
AliasesUBUNTU-CVE-2022-49090DEBIAN-CVE-2022-49090
Published 26-02-2025Last modified 11-05-2026

Vulnerability summary

CVE-2022-49090 is a medium (CVSS 5.5) NULL Pointer Dereference vulnerability in linux. EPSS estimates a 0.25% chance of exploitation in the next 30 days, higher than 15.9% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 5.5, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
5.5/10
010
Medium · v3.1 (NVD)
EPSS score
0.25%
0%100%
Low · 0.00 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 5 · Related 4

Timeline

  1. 26-02-2025
    PublishedVulnerability first disclosed.
  2. 11-05-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: arch/arm64: Fix topology initialization for core scheduling Arm64 systems rely on store_cpu_topology() to call update_siblings_masks() to transfer the toplogy to the various cpu masks. This needs to be done before the call to notify_cpu_starting() which tells the scheduler about each cpu found, otherwise the core scheduling data structures are setup in a way that does not match the actual topology. With smt_mask not setup correctly we bail on `cpumask_weight(smt_mask) == 1` for !leaders in: notify_cpu_starting() cpuhp_invoke_callback_range() sched_cpu_starting() sched_core_cpu_starting() which leads to rq->core not being correctly set for !leader-rq's. Without this change stress-ng (which enables core scheduling in its prctl tests in newer versions -- i.e. with PR_SCHED_CORE support) causes a warning and then a crash (trimmed for legibility): [ 1853.805168] ------------[ cut here ]------------ [ 1853.809784] task_rq(b)->core != rq->core [ 1853.809792] WARNING: CPU: 117 PID: 0 at kernel/sched/fair.c:11102 cfs_prio_less+0x1b4/0x1c4 ... [ 1854.015210] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010 ... [ 1854.231256] Call trace: [ 1854.233689] pick_next_task+0x3dc/0x81c [ 1854.237512] __schedule+0x10c/0x4cc [ 1854.240988] schedule_idle+0x34/0x54

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.25%

Chance of exploitation in the next 30 days

Percentile

16%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.25% 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

Affected systems

Version check

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

Ubuntu89 products
  • linux< 5.15.0-37.39
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-aws< 5.15.0-1011.14
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux2 products
  • linux≥ 9edeaea1bc452372718837ed2ba775811baf1ba1, < 87f5d66daa5f457449bb95d6b8d18bb7596aa627 | ≥ 9edeaea1bc452372718837ed2ba775811baf1ba1, < 790c1567582bda8f1153015436e3330a7c6eb278 | ≥ 9edeaea1bc452372718837ed2ba775811baf1ba1, < c78a1b2d0bff678570c8dc9f14035606f5e5257d | ≥ 9edeaea1bc452372718837ed2ba775811baf1ba1, < 5524cbb1bfcdff0cad0aaa9f94e6092002a07259 | 5.14
  • linux_kernel≥ 5.14, < 5.15.34 | ≥ 5.16, < 5.16.20 | ≥ 5.17, < 5.17.3 | 5.18:rc1
Debian1 product
  • linux< 5.17.3-1

3 vendors · 92 products

References

8 links