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NVD / CVE Program· CNA Linux

CVE-2025-21889: perf/core: Add RCU read lock protection to perf_iterate_ctx()

Noroxi assessment

Priority: Monitor (action score 22/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.20% (FIRST EPSS).
  • Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Linux Linux 0fe8813baf4b2e865d3b2c735ce1a15b86002c74, a2475ccad6120546ea45dbcd6cd1f74dc565ef6b, dd536566dda9a551fc2a2acfab5313a5bb13ed02.
  • Severity is disputed: the assigning authority (CNA) scores it 7.8, NVD 5.5.

Low priority for now. Upgrade to Linux Linux 0fe8813baf4b2e865d3b2c735ce1a15b86002c74, a2475ccad6120546ea45dbcd6cd1f74dc565ef6b, dd536566dda9a551fc2a2acfab5313a5bb13ed02 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

In the Linux kernel, the following vulnerability has been resolved: perf/core: Add RCU read lock protection to perf_iterate_ctx() The perf_iterate_ctx() function performs RCU list traversal but currently lacks RCU read lock protection. This causes lockdep warnings when running perf probe with unshare(1) under CONFIG_PROVE_RCU_LIST=y: WARNING: suspicious RCU usage kernel/events/core.c:8168 RCU-list traversed in non-reader section!! Call Trace: lockdep_rcu_suspicious ? perf_event_addr_filters_apply perf_iterate_ctx perf_event_exec begin_new_exec ? load_elf_phdrs load_elf_binary ? lock_acquire ? find_held_lock ? bprm_execve bprm_execve do_execveat_common.isra.0 __x64_sys_execve do_syscall_64 entry_SYSCALL_64_after_hwframe This protection was previously present but was removed in commit bd2756811766 ("perf: Rewrite core context handling"). Add back the necessary rcu_read_lock()/rcu_read_unlock() pair around perf_iterate_ctx() call in perf_event_exec(). [ mingo: Use scoped_guard() as suggested by Peter ]

MediumCVSS 5.5 · v3.1—No exploit Fix available
Published
Mar 27, 2025
Updated
Oct 15, 2026
EPSS
0.2% · 10th percentile
CWE
—

Report tools

JSON

Action score

22

Monitor

Low priority for now.

CVSS
22 / 40 · 5.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.2%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
5.5
CNA · Linux
7.8
2.3 point gap

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

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When you'll hear from us

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  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
linuxlinux kernel

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • linux linux kernel6.2 and later · before 6.6.81
  • linux linux kernel6.7 and later · before 6.12.18
  • linux linux kernel6.13 and later · before 6.13.6
  • linux linux kernel6.14

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

  • Linux Linux

    • 6.2affected
    • bd27568117664b8b3e259721393df420ed51f57b and later · before f390c2eea571945f357a2d3b9fcb1c015767132eaffected · git
    • bd27568117664b8b3e259721393df420ed51f57b and later · before a2475ccad6120546ea45dbcd6cd1f74dc565ef6baffected · git
    • bd27568117664b8b3e259721393df420ed51f57b and later · before dd536566dda9a551fc2a2acfab5313a5bb13ed02affected · git
    • bd27568117664b8b3e259721393df420ed51f57b and later · before 0fe8813baf4b2e865d3b2c735ce1a15b86002c74affected · git
    • before 6.2not affected · semver
    • 6.6.81 and later · up to and including 6.6.*not affected · semver
    • 6.12.18 and later · up to and including 6.12.*not affected · semver
    • 6.13.6 and later · up to and including 6.13.*not affected · semver
    • 6.14 and laternot affected · original_commit_for_fix

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:13linuxbefore 6.12.19-16.12.19-1
SUSE:Linux Micro 6.0kernel-livepatch-MICRO-6-0-RT_Update_7before 1-1.31-1.3
SUSE:Linux Micro 6.0kernel-rtbefore 6.4.0-30.16.4.0-30.1
SUSE:Linux Micro 6.0kernel-source-rtbefore 6.4.0-30.16.4.0-30.1

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
    90Now
  • CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV
    89Now
  • CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
    85Now

Published before and after this one in the same product

  • ← EarlierCVE-2025-21887Mar 27, 2025 · ovl: fix UAF in ovl_dentry_update_reval by moving dput() in ovl_link_up
    31Monitor
  • ← EarlierCVE-2025-21888Mar 27, 2025 · RDMA/mlx5: Fix a WARN during dereg_mr for DM type
    22Monitor
  • Later →CVE-2025-21890Mar 27, 2025 · idpf: fix checksums set in idpf_rx_rsc()
    22Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Linux Linux0fe8813baf4b2e865d3b2c735ce1a15b86002c74Vendor (CNA)
Linux Linuxa2475ccad6120546ea45dbcd6cd1f74dc565ef6bVendor (CNA)
Linux Linuxdd536566dda9a551fc2a2acfab5313a5bb13ed02Vendor (CNA)
Linux Linuxf390c2eea571945f357a2d3b9fcb1c015767132eVendor (CNA)
debian:linux6.12.19-1 · Debian:13Package registry (OSV)
suse:kernel-livepatch-MICRO-6-0-RT_Update_71-1.3 · SUSE:Linux Micro 6.0Package registry (OSV)
suse:kernel-rt6.4.0-30.1 · SUSE:Linux Micro 6.0Package registry (OSV)
suse:kernel-source-rt6.4.0-30.1 · SUSE:Linux Micro 6.0Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

—

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. SSVC exploitation— → none
  2. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (3 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records