<Vulnerability name="CVE-2026-64265">
    <DocumentDistribution xml:lang="en">Copyright © 2012 Red Hat, Inc. All rights reserved.</DocumentDistribution>
    <ThreatSeverity>Important</ThreatSeverity>
    <PublicDate>2026-07-25T00:00:00</PublicDate>
    <Bugzilla id="2507041" url="https://bugzilla.redhat.com/show_bug.cgi?id=2507041" xml:lang="en:us">
kernel: fuse: clear intr_entry in fuse_resend and fuse_remove_pending_req
    </Bugzilla>
    <CVSS3 status="draft">
        <CVSS3BaseScore>7.0</CVSS3BaseScore>
        <CVSS3ScoringVector>CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H</CVSS3ScoringVector>
    </CVSS3>
    <CWE>CWE-825</CWE>
    <Details xml:lang="en:us" source="Mitre">
In the Linux kernel, the following vulnerability has been resolved:

fuse: clear intr_entry in fuse_resend and fuse_remove_pending_req

When fuse_resend() moves a request from fpq-&gt;processing back to
fiq-&gt;pending, it sets FR_PENDING and clears FR_SENT but does not
remove the requests intr_entry from fiq-&gt;interrupts.  If the
request had FR_INTERRUPTED set from a prior signal, intr_entry
remains dangling on fiq-&gt;interrupts.  When the requesting task
then receives a fatal signal, fuse_remove_pending_req() sees
FR_PENDING=1, removes the request from fiq-&gt;pending and frees it
via the refcount path, also without cleaning intr_entry.  The
stale intr_entry causes use-after-free when fuse_read_interrupt()
iterates fiq-&gt;interrupts:
  - list_del_init(&amp;req-&gt;intr_entry) -&gt; UAF write on freed slab
  - req-&gt;in.h.unique -&gt; UAF read, data leaked to userspace

Remove intr_entry from fiq-&gt;interrupts in fuse_resend() for
interrupted requests before they are placed back on fiq-&gt;pending.

Add a WARN_ON if the intr_entry is not empty on request destruction.
    </Details>
    <Details xml:lang="en:us" source="Red Hat">
A flaw was found in the Linux kernel's fuse component. When a fuse request is interrupted and then resent, a specific interrupt entry (`intr_entry`) is not properly cleared. If the requesting task subsequently receives a fatal signal, this uncleared entry can lead to a use-after-free condition. This vulnerability can result in memory corruption, potentially causing a system crash, and may also lead to the disclosure of sensitive data to userspace.
    </Details>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:10">
        <ProductName>Red Hat Enterprise Linux 10</ProductName>
        <FixState>Affected</FixState>
        <PackageName>kernel</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:6">
        <ProductName>Red Hat Enterprise Linux 6</ProductName>
        <FixState>Under investigation</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-2026-64265
https://nvd.nist.gov/vuln/detail/CVE-2026-64265
https://lore.kernel.org/linux-cve-announce/2026072558-CVE-2026-64265-5f6c@gregkh/T
    </References>
</Vulnerability>