NVD / CVE Program· CNA Linux

CVE-2023-52935: mm/khugepaged: fix ->anon_vma race

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: 0.19% (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 023f47a8250c6bdb4aebe744db4bf7f73414028b, 352fbf61ce776fef18dca6a68680a6cd943dac95, abdf3c33918185c3e8ffeb09ed3e334b3d7df47c; cbl2 kernel 5.15.186.1-1 on CBL Mariner 2.0 5.15.200.1-1; cbl2 kernel 5.15.186.1-1 on CBL-Mariner 2.0 5.15.200.1-1.

Low priority for now. Upgrade to Linux Linux 023f47a8250c6bdb4aebe744db4bf7f73414028b, 352fbf61ce776fef18dca6a68680a6cd943dac95, abdf3c33918185c3e8ffeb09ed3e334b3d7df47c; cbl2 kernel 5.15.186.1-1 on CBL Mariner 2.0 5.15.200.1-1; cbl2 kernel 5.15.186.1-1 on CBL-Mariner 2.0 5.15.200.1-1 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: mm/khugepaged: fix ->anon_vma race If an ->anon_vma is attached to the VMA, collapse_and_free_pmd() requires it to be locked. Page table traversal is allowed under any one of the mmap lock, the anon_vma lock (if the VMA is associated with an anon_vma), and the mapping lock (if the VMA is associated with a mapping); and so to be able to remove page tables, we must hold all three of them. retract_page_tables() bails out if an ->anon_vma is attached, but does this check before holding the mmap lock (as the comment above the check explains). If we racily merged an existing ->anon_vma (shared with a child process) from a neighboring VMA, subsequent rmap traversals on pages belonging to the child will be able to see the page tables that we are concurrently removing while assuming that nothing else can access them. Repeat the ->anon_vma check once we hold the mmap lock to ensure that there really is no concurrent page table access. Hitting this bug causes a lockdep warning in collapse_and_free_pmd(), in the line "lockdep_assert_held_write(&vma->anon_vma->root->rwsem)". It can also lead to use-after-free access.

HighCVSS 7.8 · v3.1—No exploit Fix available

Memory safety

Published: Mar 27, 2025
Updated: Aug 5, 2026
EPSS: 0.1% · 9th 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 · 0.1%

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.

Running WordPress? Scan your site free with WP Lens

Is your version affected? Check it

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.

We use this product, ask for help

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
debian	debian linux	cpe:2.3:o:debian:debian_linux

Affected versions

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

debian debian linux11.0
linux linux kernel4.8 and later · before 5.4.299
linux linux kernel5.5 and later · before 5.10.243
linux linux kernel5.11 and later · before 5.15.192
linux linux kernel5.16 and later · before 6.1.11
linux linux kernel6.2

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
- 4.8affected
- 5.4.299 and later · up to and including 5.4.*not affected · semver
- f3f0e1d2150b2b99da2cbdfaad000089efe9bf30 and later · before 352fbf61ce776fef18dca6a68680a6cd943dac95affected · git
- f3f0e1d2150b2b99da2cbdfaad000089efe9bf30 and later · before cee956ab1efbd858b4ca61c8b474af5aa24b29a6affected · git
- f3f0e1d2150b2b99da2cbdfaad000089efe9bf30 and later · before abdf3c33918185c3e8ffeb09ed3e334b3d7df47caffected · git
- f3f0e1d2150b2b99da2cbdfaad000089efe9bf30 and later · before acb08187b5a83cdb9ac4112fae9e18cf983b0128affected · git
- f3f0e1d2150b2b99da2cbdfaad000089efe9bf30 and later · before 023f47a8250c6bdb4aebe744db4bf7f73414028baffected · git
- before 4.8not affected · semver
- 5.10.243 and later · up to and including 5.10.*not affected · semver
- 5.15.192 and later · up to and including 5.15.*not affected · semver

Package-level exposure

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

Ecosystem	Package	Affected range	Fix
Debian:11	linux	before 5.10.244-1	5.10.244-1
Debian:12	linux	before 6.1.11-1	6.1.11-1

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-2023-52933Mar 27, 2025 · Squashfs: fix handling and sanity checking of xattr_ids count
22Monitor
← EarlierCVE-2023-52934Mar 27, 2025 · mm/MADV_COLLAPSE: catch !none !huge !bad pmd lookups
18Monitor
Later →CVE-2023-52936Mar 27, 2025 · kernel/irq/irqdomain.c: fix memory leak with using debugfs_lookup()
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	023f47a8250c6bdb4aebe744db4bf7f73414028b	Vendor (CNA)
Linux Linux	352fbf61ce776fef18dca6a68680a6cd943dac95	Vendor (CNA)
Linux Linux	abdf3c33918185c3e8ffeb09ed3e334b3d7df47c	Vendor (CNA)
Linux Linux	acb08187b5a83cdb9ac4112fae9e18cf983b0128	Vendor (CNA)
Linux Linux	cee956ab1efbd858b4ca61c8b474af5aa24b29a6	Vendor (CNA)
cbl2 kernel 5.15.186.1-1 on CBL Mariner 2.0	5.15.200.1-1 · CBL-Mariner Releases	Microsoft (MSRC)
cbl2 kernel 5.15.186.1-1 on CBL-Mariner 2.0	5.15.200.1-1 · CBL-Mariner Releases	Microsoft (MSRC)
debian:linux	6.1.11-1 · 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, 10:11 PM UTC

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

References

git.kernel.org/stable/c/023f47a8250c6bdb4aebe744db4bf7f73414028b

Show all references (5 more)

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

All records