7

CVE-2026-46029: mm/slab: return NULL early from kmalloc_nolock() in NMI on UP

Analyzed
AliasesUBUNTU-CVE-2026-46029DEBIAN-CVE-2026-46029
Published 27-05-2026Last modified 05-08-2026

Vulnerability summary

CVE-2026-46029 is a high (CVSS 7.0) vulnerability in linux. EPSS estimates a 0.15% chance of exploitation in the next 30 days, higher than 3.9% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 7, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
7.0/10
010
High · v3.1 (CVE.org)
EPSS score
0.15%
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 7 · Related 7
OPENSUSE-SU-2026:10954-1USN-8488-1USN-8488-2USN-8489-1USN-8507-1USN-8569-1

Timeline

  1. 27-05-2026
    PublishedVulnerability first disclosed.
  2. 05-08-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: mm/slab: return NULL early from kmalloc_nolock() in NMI on UP On UP kernels (!CONFIG_SMP), spin_trylock() is a no-op that unconditionally succeeds even when the lock is already held. As a result, kmalloc_nolock() called from NMI context can re-enter the slab allocator and acquire n->list_lock that the interrupted context is already holding, corrupting slab state. With CONFIG_DEBUG_SPINLOCK on UP, the following BUG is triggered with the slub_kunit test module: BUG: spinlock trylock failure on UP on CPU#0, kunit_try_catch/243 [...] Call Trace: <NMI> dump_stack_lvl+0x3f/0x60 do_raw_spin_trylock+0x41/0x50 _raw_spin_trylock+0x24/0x50 get_from_partial_node+0x120/0x4d0 ___slab_alloc+0x8a/0x4c0 kmalloc_nolock_noprof+0x164/0x310 [...] </NMI> Fix this by returning NULL early when invoked from NMI on a UP kernel.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.15%

Chance of exploitation in the next 30 days

Percentile

4%

Versus all other CVEs

30-day change

Decrease -0.01 pp

From 0.15% 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.

Ubuntu99 products
  • linux< 7.0.0-27.27
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-aws< 7.0.0-1008.8
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux2 products
  • linux≥ af92793e52c3a99b828ed4bdd277fd3e11c18d08, < a8d95d274be241ad21f6523bf2d6ba0d7d7e46b7 | ≥ af92793e52c3a99b828ed4bdd277fd3e11c18d08, < d66553204a15bdb257d9ef8aca1e12f5fbb910b2 | ≥ af92793e52c3a99b828ed4bdd277fd3e11c18d08, < 5b31044e649e3e54c2caef135c09b371c2fbcd08 | 6.18
  • linux_kernel≥ 6.18, < 6.18.27 | ≥ 6.19, < 7.0.4 | 7.1:rc1
Debian1 product
  • linux< 7.0.4-1

3 vendors · 102 products

References

13 links
Show all 13 references