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NVD / CVE Program· CNA Linux

CVE-2021-47087: tee: optee: Fix incorrect page free bug

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: 0.23% (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 18549bf4b21c739a9def39f27dcac53e27286ab5, 5.10.89, 5.14.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Linux Linux 18549bf4b21c739a9def39f27dcac53e27286ab5, 5.10.89, 5.14 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: tee: optee: Fix incorrect page free bug Pointer to the allocated pages (struct page *page) has already progressed towards the end of allocation. It is incorrect to perform __free_pages(page, order) using this pointer as we would free any arbitrary pages. Fix this by stop modifying the page pointer.

HighCVSS 7.8 · v3.1—No exploit Fix available
Published
Mar 4, 2024
Updated
Aug 5, 2026
EPSS
0.2% · 14th percentile

Report tools

JSON

Action score

31

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
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
7.8
CNA · Linux
7.8
agree

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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When you'll hear from us

  • when it enters CISA KEV
  • 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 kernel5.4.140 and later · before 5.4.169
  • linux linux kernel5.10.58 and later · before 5.10.89
  • linux linux kernel5.14 and later · before 5.15.12
  • linux linux kernel5.16

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

    • 255e17923b22cb7abd026e044416d61f6bd0eec0, 5.14affected
    • 3c712f14d8a9354a8807c15c64c8dd334499cc42 and later · before 806142c805cacd098e61bdc0f72c778a2389fe4aaffected · git
    • 1340dc3fb75ea69221f4f5dcb0cbace55ad0331c and later · before ad338d825e3f7b96ee542bf313728af2d19fe9adaffected · git
    • ec185dd3ab257dc2a60953fdf1b6622f524cc5b7 and later · before 91e94e42f6fc49635f1a16d8ae3f79552bcfda29affected · git
    • ec185dd3ab257dc2a60953fdf1b6622f524cc5b7 and later · before 18549bf4b21c739a9def39f27dcac53e27286ab5affected · git
    • 5.4.140 and later · before 5.4.169affected · semver
    • 5.10.58 and later · before 5.10.89affected · semver
    • 5.13.10 and later · before 5.14affected · semver
    • before 5.14not affected · semver
    • 5.4.169 and later · up to and including 5.4.*not affected · semver

Package-level exposure

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

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 5.15.15-15.15.15-1
openSUSE:Leap 15.5dtb-aarch64before 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap 15.5kernel-64kbbefore 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap 15.5kernel-azurebefore 5.14.21-150500.33.48.15.14.21-150500.33.48.1
openSUSE:Leap 15.5kernel-debugbefore 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap 15.5kernel-defaultbefore 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap 15.5kernel-default-basebefore 5.14.21-150500.55.59.1.150500.6.25.75.14.21-150500.55.59.1.150500.6.25.7
openSUSE:Leap 15.5kernel-docsbefore 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap 15.5kernel-kvmsmallbefore 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap 15.5kernel-obs-buildbefore 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap 15.5kernel-obs-qabefore 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap 15.5kernel-rtbefore 5.14.21-150500.13.47.15.14.21-150500.13.47.1
openSUSE:Leap 15.5kernel-rt_debugbefore 5.14.21-150500.13.47.15.14.21-150500.13.47.1
openSUSE:Leap 15.5kernel-sourcebefore 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap 15.5kernel-source-azurebefore 5.14.21-150500.33.48.15.14.21-150500.33.48.1
openSUSE:Leap 15.5kernel-source-rtbefore 5.14.21-150500.13.47.15.14.21-150500.13.47.1
openSUSE:Leap 15.5kernel-symsbefore 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap 15.5kernel-syms-azurebefore 5.14.21-150500.33.48.15.14.21-150500.33.48.1
openSUSE:Leap 15.5kernel-syms-rtbefore 5.14.21-150500.13.47.15.14.21-150500.13.47.1
openSUSE:Leap 15.5kernel-zfcpdumpbefore 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap Micro 5.3kernel-defaultbefore 5.14.21-150400.24.116.15.14.21-150400.24.116.1
openSUSE:Leap Micro 5.3kernel-default-basebefore 5.14.21-150400.24.116.1.150400.24.54.55.14.21-150400.24.116.1.150400.24.54.5
openSUSE:Leap Micro 5.3kernel-rtbefore 5.14.21-150400.15.76.15.14.21-150400.15.76.1
SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOSkernel-64kbbefore 5.14.21-150400.24.116.15.14.21-150400.24.116.1

+27

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-2021-47083Mar 4, 2024 · pinctrl: mediatek: fix global-out-of-bounds issue
    28Monitor
  • ← EarlierCVE-2021-47086Mar 4, 2024 · phonet/pep: refuse to enable an unbound pipe
    22Monitor
  • Later →CVE-2021-47088Mar 4, 2024 · mm/damon/dbgfs: protect targets destructions with kdamond_lock
    28Monitor

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 Linux18549bf4b21c739a9def39f27dcac53e27286ab5Vendor (CNA)
Linux Linux5.10.89Vendor (CNA)
Linux Linux5.14Vendor (CNA)
Linux Linux5.4.169Vendor (CNA)
Linux Linux806142c805cacd098e61bdc0f72c778a2389fe4aVendor (CNA)
Linux Linux91e94e42f6fc49635f1a16d8ae3f79552bcfda29Vendor (CNA)
Linux Linuxad338d825e3f7b96ee542bf313728af2d19fe9adVendor (CNA)
debian:linux5.15.15-1 · Debian:12Package registry (OSV)
opensuse:dtb-aarch645.14.21-150500.55.59.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-64kb5.14.21-150500.55.59.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-debug5.14.21-150500.55.59.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-default5.14.21-150400.24.116.1 · openSUSE:Leap Micro 5.3Package registry (OSV)
opensuse:kernel-default-base5.14.21-150400.24.116.1.150400.24.54.5 · openSUSE:Leap Micro 5.3Package registry (OSV)
opensuse:kernel-docs5.14.21-150500.55.59.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-kvmsmall5.14.21-150500.55.59.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-obs-build5.14.21-150500.55.59.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-rt5.14.21-150400.15.76.1 · openSUSE:Leap Micro 5.3Package registry (OSV)
opensuse:kernel-rt_debug5.14.21-150500.13.47.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-source-rt5.14.21-150500.13.47.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-syms-rt5.14.21-150500.13.47.1 · openSUSE:Leap 15.5Package registry (OSV)
suse:kernel-64kb5.14.21-150400.24.116.1 · SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOSPackage registry (OSV)
suse:kernel-default5.14.21-150400.24.116.1 · SUSE:Linux Enterprise Micro 5.3Package registry (OSV)
suse:kernel-default-base5.14.21-150400.24.116.1.150400.24.54.5 · SUSE:Linux Enterprise Micro 5.3Package registry (OSV)
suse:kernel-docs5.14.21-150400.24.116.1 · SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOSPackage registry (OSV)
suse:kernel-livepatch-SLE15-SP4_Update_251-150400.9.5.1 · SUSE:Linux Enterprise Live Patching 15 SP4Package registry (OSV)
suse:kernel-livepatch-SLE15-SP5-RT_Update_131-150500.11.3.1 · SUSE:Linux Enterprise Live Patching 15 SP5Package registry (OSV)
suse:kernel-obs-build5.14.21-150400.24.116.1 · SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOSPackage registry (OSV)
suse:kernel-rt5.14.21-150400.15.76.1 · SUSE:Linux Enterprise Micro 5.3Package registry (OSV)
suse:kernel-source5.14.21-150400.24.116.1 · SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOSPackage registry (OSV)
suse:kernel-source-rt5.14.21-150400.15.76.1 · SUSE:Linux Enterprise Micro 5.3Package registry (OSV)

+2

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.

  • CVE-2022-48425352 days apartIn the Linux kernel through 6.2.7, fs/ntfs3/inode.c has an invalid kfree because it does not validate MFT flags before replaying logs.
    31Monitor
  • CVE-2022-4696418 days apartThere exists a use-after-free vulnerability in the Linux kernel through io_uring and the IORING_OP_SPLICE operation.
    31Monitor
  • CVE-2024-42132148 days apartbluetooth/hci: disallow setting handle bigger than HCI_CONN_HANDLE_MAX
    28Monitor
  • CVE-2024-3583274 days apartbcachefs: kvfree bch_fs::snapshots in bch2_fs_snapshots_exit
    22Monitor
  • CVE-2021-4722178 days apartmm/slub: actually fix freelist pointer vs redzoning
    22Monitor
  • CVE-2021-4738778 days apartcpufreq: schedutil: Use kobject release() method to free sugov_tunables
    22Monitor

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).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

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-763 · Release of Invalid Pointer or Reference

CVSS vector

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