<Vulnerability name="CVE-2026-53273">
    <DocumentDistribution xml:lang="en">Copyright © 2012 Red Hat, Inc. All rights reserved.</DocumentDistribution>
    <PublicDate>2026-06-25T00:00:00</PublicDate>
    <Bugzilla id="2492744" url="https://bugzilla.redhat.com/show_bug.cgi?id=2492744" xml:lang="en:us">
kernel: tee: optee: prevent use-after-free when the client exits before the supplicant
    </Bugzilla>
    <CWE>CWE-825</CWE>
    <Details xml:lang="en:us" source="Mitre">
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-&gt;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-&gt;mutex:

  * Hold supp-&gt;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.
    </Details>
    <Details xml:lang="en:us" source="Red Hat">
A flaw was found in the Linux kernel's Trusted Execution Environment (TEE) subsystem, specifically within the OP-TEE driver. This use-after-free vulnerability occurs when a client task terminates before its associated supplicant has finished processing a request. This timing issue can lead to the system attempting to access memory that has already been freed, potentially resulting in a denial of service or arbitrary code execution.
    </Details>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:10">
        <ProductName>Red Hat Enterprise Linux 10</ProductName>
        <FixState>Not affected</FixState>
        <PackageName>kernel</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:6">
        <ProductName>Red Hat Enterprise Linux 6</ProductName>
        <FixState>Not affected</FixState>
        <PackageName>kernel</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:7">
        <ProductName>Red Hat Enterprise Linux 7</ProductName>
        <FixState>Not affected</FixState>
        <PackageName>kernel</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:7">
        <ProductName>Red Hat Enterprise Linux 7</ProductName>
        <FixState>Not affected</FixState>
        <PackageName>kernel-rt</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:8">
        <ProductName>Red Hat Enterprise Linux 8</ProductName>
        <FixState>Not affected</FixState>
        <PackageName>kernel</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:8">
        <ProductName>Red Hat Enterprise Linux 8</ProductName>
        <FixState>Not affected</FixState>
        <PackageName>kernel-rt</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:9">
        <ProductName>Red Hat Enterprise Linux 9</ProductName>
        <FixState>Not affected</FixState>
        <PackageName>kernel</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:9">
        <ProductName>Red Hat Enterprise Linux 9</ProductName>
        <FixState>Not affected</FixState>
        <PackageName>kernel-rt</PackageName>
    </PackageState>
    <References xml:lang="en:us">
https://www.cve.org/CVERecord?id=CVE-2026-53273
https://nvd.nist.gov/vuln/detail/CVE-2026-53273
https://lore.kernel.org/linux-cve-announce/2026062519-CVE-2026-53273-8e6b@gregkh/T
    </References>
</Vulnerability>