NVD / CVE Program· CNA Linux

CVE-2024-58083: KVM: Explicitly verify target vCPU is online in kvm_get_vcpu()

Noroxi assessment

Priority: Monitor (action score 31/100)

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: 0.22% (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 09d50ccf0b2d739db4a485b08afe7520a4402a63, 125da53b3c0c9d7f58353aea0076e9efd6498ba7, 1e7381f3617d14b3c11da80ff5f8a93ab14cfc46; cbl2 kernel 5.15.176.3-3 on CBL Mariner 2.0 5.15.180.1-1; cbl2 kernel 5.15.176.3-3 on CBL-Mariner 2.0 5.15.180.1-1.

Low priority for now. Upgrade to Linux Linux 09d50ccf0b2d739db4a485b08afe7520a4402a63, 125da53b3c0c9d7f58353aea0076e9efd6498ba7, 1e7381f3617d14b3c11da80ff5f8a93ab14cfc46; cbl2 kernel 5.15.176.3-3 on CBL Mariner 2.0 5.15.180.1-1; cbl2 kernel 5.15.176.3-3 on CBL-Mariner 2.0 5.15.180.1-1 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: KVM: Explicitly verify target vCPU is online in kvm_get_vcpu() Explicitly verify the target vCPU is fully online _prior_ to clamping the index in kvm_get_vcpu(). If the index is "bad", the nospec clamping will generate '0', i.e. KVM will return vCPU0 instead of NULL. In practice, the bug is unlikely to cause problems, as it will only come into play if userspace or the guest is buggy or misbehaving, e.g. KVM may send interrupts to vCPU0 instead of dropping them on the floor. However, returning vCPU0 when it shouldn't exist per online_vcpus is problematic now that KVM uses an xarray for the vCPUs array, as KVM needs to insert into the xarray before publishing the vCPU to userspace (see commit c5b077549136 ("KVM: Convert the kvm->vcpus array to a xarray")), i.e. before vCPU creation is guaranteed to succeed. As a result, incorrectly providing access to vCPU0 will trigger a use-after-free if vCPU0 is dereferenced and kvm_vm_ioctl_create_vcpu() bails out of vCPU creation due to an error and frees vCPU0. Commit afb2acb2e3a3 ("KVM: Fix vcpu_array[0] races") papered over that issue, but in doing so introduced an unsolvable teardown conundrum. Preventing accesses to vCPU0 before it's fully online will allow reverting commit afb2acb2e3a3, without re-introducing the vcpu_array[0] UAF race.

HighCVSS 7.8 · v3.1—No exploit Fix available

Memory safety

BDU:2025-12082

Published: Mar 6, 2025
Updated: Oct 15, 2026
EPSS: 0.2% · 13th percentile
CWE: CWE-416

Report tools

JSON

Action score

Monitor

Low priority for now.

CVSS: 31 / 40 · 7.8 / 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: —
CNA · Linux: 7.8; NVD has not scored this yet; the score shown is the CNA’s.

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

If any of these changes, we'll tell you in the daily email digest.

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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.

Vendor	Product	CPE
linux	linux kernel	cpe:2.3:o:linux:linux_kernel

Affected versions

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

linux linux kernel4.14.120 and later · before 4.15
linux linux kernel4.19.44 and later · before 4.20
linux linux kernel5.0.17 and later · before 5.4.291
linux linux kernel5.5 and later · before 5.10.235
linux linux kernel5.11 and later · before 5.15.179
linux linux kernel5.16 and later · before 6.1.129
linux linux kernel6.2 and later · before 6.6.78
linux linux kernel6.7 and later · before 6.12.14
linux linux kernel6.13 and later · before 6.13.3

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
- 559e2696d2f47a3575e9550f101a7e59e30b1b38, d39f3cc71382165bb7efb8e06a2bd32f847de4ae, 7cee966029037a183d98cb88251ceb92a233fe63, 5.1affected
- 1d487e9bf8ba66a7174c56a0029c54b1eca8f99c and later · before 5cce2ed69b00e022b5cdf0c49c82986abd2941a8affected · git
- 1d487e9bf8ba66a7174c56a0029c54b1eca8f99c and later · before 09d50ccf0b2d739db4a485b08afe7520a4402a63affected · git
- 1d487e9bf8ba66a7174c56a0029c54b1eca8f99c and later · before 7c4899239d0f70f88ac42665b3da51678d122480affected · git
- 1d487e9bf8ba66a7174c56a0029c54b1eca8f99c and later · before d817e510662fd1c9797952408d94806f97a5fffdaffected · git
- 1d487e9bf8ba66a7174c56a0029c54b1eca8f99c and later · before 125da53b3c0c9d7f58353aea0076e9efd6498ba7affected · git
- 1d487e9bf8ba66a7174c56a0029c54b1eca8f99c and later · before f2f805ada63b536bc192458a7098388286568ad4affected · git
- 1d487e9bf8ba66a7174c56a0029c54b1eca8f99c and later · before ca8da90ed1432ff3d000de4f1e2275d4e7d21b96affected · git
- 1d487e9bf8ba66a7174c56a0029c54b1eca8f99c and later · before 1e7381f3617d14b3c11da80ff5f8a93ab14cfc46affected · git
- 4.14.120 and later · before 4.15affected · semver

Package-level exposure

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

Ecosystem	Package	Affected range	Fix
Debian:12	linux	before 6.1.129-1	6.1.129-1
Debian:13	linux	before 6.12.15-1	6.12.15-1

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-2024-58078Mar 6, 2025 · misc: misc_minor_alloc to use ida for all dynamic/misc dynamic minors
22Monitor
← EarlierCVE-2024-58079Mar 6, 2025 · media: uvcvideo: Fix crash during unbind if gpio unit is in use
22Monitor
Later →CVE-2024-58085Mar 6, 2025 · tomoyo: don't emit warning in tomoyo_write_control()
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 / package	Fixed version	Source
Linux Linux	09d50ccf0b2d739db4a485b08afe7520a4402a63	Vendor (CNA)
Linux Linux	125da53b3c0c9d7f58353aea0076e9efd6498ba7	Vendor (CNA)
Linux Linux	1e7381f3617d14b3c11da80ff5f8a93ab14cfc46	Vendor (CNA)
Linux Linux	4.15	Vendor (CNA)
Linux Linux	4.20	Vendor (CNA)
Linux Linux	5.1	Vendor (CNA)
Linux Linux	5cce2ed69b00e022b5cdf0c49c82986abd2941a8	Vendor (CNA)
Linux Linux	7c4899239d0f70f88ac42665b3da51678d122480	Vendor (CNA)
Linux Linux	ca8da90ed1432ff3d000de4f1e2275d4e7d21b96	Vendor (CNA)
Linux Linux	d817e510662fd1c9797952408d94806f97a5fffd	Vendor (CNA)
Linux Linux	f2f805ada63b536bc192458a7098388286568ad4	Vendor (CNA)
cbl2 kernel 5.15.176.3-3 on CBL Mariner 2.0	5.15.180.1-1 · CBL-Mariner Releases	Microsoft (MSRC)
cbl2 kernel 5.15.176.3-3 on CBL-Mariner 2.0	5.15.180.1-1 · CBL-Mariner Releases	Microsoft (MSRC)
cbl2 kernel 5.15.180.1-1 on CBL Mariner 2.0	5.15.180.1-1 · CBL-Mariner Releases	Microsoft (MSRC)
debian:linux	6.1.129-1 · Debian:12	Package 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: high · data can be read
Integrity: high · data or configuration can be modified
Availability: high · the service can be disrupted

Attack vector: Local
Attack complexity: Low
Privileges required: Low
User interaction: None
Scope: Unchanged
Confidentiality impact: High
Integrity impact: High
Availability impact: High

Weakness class (CWE)

CWE-416 · Use After Free

CVSS vector

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

nvd-secondary

Root cause

After a memory region is freed, another reference pointing to it is still used. By then, the same region may have been allocated for different data.

The bug in code

The whole CWE-416 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1free(dev->buf);
2/* ... another thread is still running ... */
3process(dev->buf);

Fixed

1lock(&dev->lock);
2free(dev->buf);
3dev->buf = NULL;
4unlock(&dev->lock);

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

Fix✗ → ✓Sep 28, 2026, 10:10 PM UTC

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

References

git.kernel.org/stable/c/09d50ccf0b2d739db4a485b08afe7520a4402a63

Show all references (10 more)

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

All records