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NVD / CVE Program· CNA Linux

CVE-2026-53273: tee: optee: prevent use-after-free when the client exits before the supplicant

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: 0.15% (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 373152c94e57e9592b68c100e224fbd943cfd608, 387a926ee166814611acecb960207fe2f3c4fd3e, 416259cb5bffecaaae5f76539deb535a8c1b2c34.

Low priority for now. Upgrade to Linux Linux 373152c94e57e9592b68c100e224fbd943cfd608, 387a926ee166814611acecb960207fe2f3c4fd3e, 416259cb5bffecaaae5f76539deb535a8c1b2c34 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: prevent use-after-free when the client exits before the supplicant Commit 70b0d6b0a199 ("tee: optee: Fix supplicant wait loop") made the client wait as killable so it can be interrupted during shutdown or after a supplicant crash. This changes the original lifetime expectations: the client task can now terminate while the supplicant is still processing its request. If the client exits first it removes the request from its queue and kfree()s it, while the request ID remains in supp->idr. A subsequent lookup on the supplicant path then dereferences freed memory, leading to a use-after-free. Serialise access to the request with supp->mutex: * Hold supp->mutex in optee_supp_recv() and optee_supp_send() while looking up and touching the request. * Let optee_supp_thrd_req() notice that the client has terminated and signal optee_supp_send() accordingly. With these changes the request cannot be freed while the supplicant still has a reference, eliminating the race.

HighCVSS 7.8 · v3.1—No exploit Fix available
Published
Jun 25, 2026
Updated
Oct 19, 2026
EPSS
0.1% · 4th 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 · 0.1%

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.

Follow CVE-2026-53273

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 kernel5.4.291 and later · before 5.5
  • linux linux kernel5.10.235 and later · before 5.10.259
  • linux linux kernel5.15.179 and later · before 5.15.210
  • linux linux kernel6.1.130 and later · before 6.1.176
  • linux linux kernel6.6.80 and later · before 6.6.143
  • linux linux kernel6.12.17 and later · before 6.12.94
  • linux linux kernel6.13.5 and later · before 6.14
  • linux linux kernel6.14.1 and later · before 6.18.36
  • linux linux kernel6.19 and later · before 7.0.13
  • linux linux kernel6.14
  • linux linux kernel7.1

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

    • 3eb4911364c764572e9db4ab900a57689a54e8ce, 21234efe2a8474a6d2d01ea9573319de7858ce44, 6.14affected
    • 0180cf0373f84fff61b16f8c062553a13dd7cfca and later · before 416259cb5bffecaaae5f76539deb535a8c1b2c34affected · git
    • c0a9a948159153be145f9471435695373904ee6d and later · before 724d0caffd4204b46f78efe22f18f8338031c6e1affected · git
    • ec18520f5edc20a00c34a8c9fdd6507c355e880f and later · before ae847ab29ded2d7cece4d5970f0edefa4137bf2faffected · git
    • d61cc1a435e6894bfb0dd3370c6f765d2d12825d and later · before 9a0dc9279d0907b198f205a693aedf696b08145daffected · git
    • fd9d2d6124c293e40797a080adf8a9c237efd8b8 and later · before d366a01475f927402c96a3fe78bfc06b924fc87daffected · git
    • 70b0d6b0a199c5a3ee6c72f5e61681ed6f759612 and later · before d5b57bb314d79e99bebb58a53588fa11dd4dbf69affected · git
    • 70b0d6b0a199c5a3ee6c72f5e61681ed6f759612 and later · before 373152c94e57e9592b68c100e224fbd943cfd608affected · git
    • 70b0d6b0a199c5a3ee6c72f5e61681ed6f759612 and later · before 387a926ee166814611acecb960207fe2f3c4fd3eaffected · git
    • 5.10.235 and later · before 5.10.259affected · semver

Package-level exposure

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

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 6.1.176-16.1.176-1
Debian:13linuxbefore 6.12.94-16.12.94-1
Debian:14linuxbefore 7.0.13-17.0.13-1

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-2026-53270Jun 25, 2026 · ipvs: clear the svc scheduler ptr early on edit
    31Monitor
  • ← EarlierCVE-2026-53272Jun 25, 2026 · erofs: fix use-after-free on sbi->sync_decompress
    31Monitor
  • Later →CVE-2026-53275Jun 25, 2026 · ipv6: mcast: Fix use-after-free when processing MLD queries
    35Monitor

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 Linux373152c94e57e9592b68c100e224fbd943cfd608Vendor (CNA)
Linux Linux387a926ee166814611acecb960207fe2f3c4fd3eVendor (CNA)
Linux Linux416259cb5bffecaaae5f76539deb535a8c1b2c34Vendor (CNA)
Linux Linux5.10.259Vendor (CNA)
Linux Linux5.15.210Vendor (CNA)
Linux Linux5.5Vendor (CNA)
Linux Linux6.1.176Vendor (CNA)
Linux Linux6.12.94Vendor (CNA)
Linux Linux6.14Vendor (CNA)
Linux Linux6.6.143Vendor (CNA)
Linux Linux724d0caffd4204b46f78efe22f18f8338031c6e1Vendor (CNA)
Linux Linux9a0dc9279d0907b198f205a693aedf696b08145dVendor (CNA)
Linux Linuxae847ab29ded2d7cece4d5970f0edefa4137bf2fVendor (CNA)
Linux Linuxd366a01475f927402c96a3fe78bfc06b924fc87dVendor (CNA)
Linux Linuxd5b57bb314d79e99bebb58a53588fa11dd4dbf69Vendor (CNA)
debian:linux6.1.176-1 · Debian:12Package 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

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

Fixed

c
lock(&dev->lock);free(dev->buf);dev->buf = NULL;unlock(&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

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

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

References

Show all references (7 more)

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

All records