Linux Kernel up to 5.15.81/6.0.2 copy_page.S mte_sync_tags privilege escalation

CVSS Meta Temp Score
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CTI Interest Score
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5.3$0-$5k1.20

Summaryinfo

A vulnerability was found in Linux Kernel up to 5.15.81/6.0.2. It has been declared as problematic. This vulnerability affects the function mte_sync_tags in the library arch/arm64/lib/copy_page.S. Executing a manipulation can lead to an unknown weakness. This vulnerability is tracked as CVE-2022-50675. No exploit exists. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.15.81/6.0.2. It has been declared as problematic. This vulnerability affects the function mte_sync_tags in the library arch/arm64/lib/copy_page.S. The impact remains unknown. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: arm64: mte: Avoid setting PG_mte_tagged if no tags cleared or restored Prior to commit 69e3b846d8a7 ("arm64: mte: Sync tags for pages where PTE is untagged"), mte_sync_tags() was only called for pte_tagged() entries (those mapped with PROT_MTE). Therefore mte_sync_tags() could safely use test_and_set_bit(PG_mte_tagged, &page->flags) without inadvertently setting PG_mte_tagged on an untagged page. The above commit was required as guests may enable MTE without any control at the stage 2 mapping, nor a PROT_MTE mapping in the VMM. However, the side-effect was that any page with a PTE that looked like swap (or migration) was getting PG_mte_tagged set automatically. A subsequent page copy (e.g. migration) copied the tags to the destination page even if the tags were owned by KASAN. This issue was masked by the page_kasan_tag_reset() call introduced in commit e5b8d9218951 ("arm64: mte: reset the page tag in page->flags"). When this commit was reverted (20794545c146), KASAN started reporting access faults because the overriding tags in a page did not match the original page->flags (with CONFIG_KASAN_HW_TAGS=y): BUG: KASAN: invalid-access in copy_page+0x10/0xd0 arch/arm64/lib/copy_page.S:26 Read at addr f5ff000017f2e000 by task syz-executor.1/2218 Pointer tag: [f5], memory tag: [f2] Move the PG_mte_tagged bit setting from mte_sync_tags() to the actual place where tags are cleared (mte_sync_page_tags()) or restored (mte_restore_tags()).

The advisory is available at git.kernel.org. This vulnerability was named CVE-2022-50675 since 12/09/2025. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 03/29/2026).

Upgrading to version 5.15.82 or 6.0.3 eliminates this vulnerability. Applying the patch 918002bdbe4328c8c0164a22e8ebf2384b80dc23/749e9fc18b1e1a3f93a9512e91bd7f93002d2821/a8e5e5146ad08d794c58252bab00b261045ef16d is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2025-2765). Once again VulDB remains the best source for vulnerability data.

Affected

  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • Open Source Linux Kernel
  • RESF Rocky Linux

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Privilege escalation
CWE: Unknown
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.15.82/6.0.3
Patch: 918002bdbe4328c8c0164a22e8ebf2384b80dc23/749e9fc18b1e1a3f93a9512e91bd7f93002d2821/a8e5e5146ad08d794c58252bab00b261045ef16d

Timelineinfo

12/09/2025 Advisory disclosed
12/09/2025 +0 days CVE reserved
12/09/2025 +0 days VulDB entry created
03/29/2026 +110 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2022-50675 (🔒)
GCVE (CVE): GCVE-0-2022-50675
GCVE (VulDB): GCVE-100-334942
CERT Bund: WID-SEC-2025-2765 - Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service

Entryinfo

Created: 12/09/2025 07:54
Updated: 03/29/2026 08:36
Changes: 12/09/2025 07:54 (57), 03/29/2026 08:36 (7)
Complete: 🔍
Cache ID: 216:8B2:103

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