CVE-2021-47644

Service interruption via Zoran teardown memory leak

Published Feb 26, 2025 · Updated Aug 26, 2026

The published CVE describes a Linux Zoran media driver leak in 5.10 through 5.17 that allows local users to interrupt service. The affected teardown path unregisters zr->video_dev without an explicit kfree(), which the CVE treats as leaving its video_device allocation unreleased. Reachability requires a ZR36057 or ZR36067 PCI capture card and local device teardown; subsequent upstream review found that the unregister call already frees the object and therefore disputes the leak.

CVSS severity5.5
Medium
EPSS probability0.25%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

The published CVE describes a Linux Zoran media driver leak in 5.10 through 5.17 that allows local users to interrupt service. The affected teardown path unregisters zr->video_dev without an explicit kfree(), which the CVE treats as leaving its video_device allocation unreleased. Reachability requires a ZR36057 or ZR36067 PCI capture card and local device teardown; subsequent upstream review found that the unregister call already frees the object and therefore disputes the leak.

The record

CVE
CVE-2021-47644
Published
Feb 26, 2025
Updated
Aug 26, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-401, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 26, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 26, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <8dce4b265a5357731058f69645840dabc718c687
  2. Affected versionversion=2.6.12
  3. Affected versionversion=5.10
  4. Affected versionversion=61c3b19f7b9eb7c7838fd35f86566230fefd6550 <1e501ec38796f43e995731d1bcd4173cb1ccfce0
  5. Affected versionversion=61c3b19f7b9eb7c7838fd35f86566230fefd6550 <82e3a496eb56da0b9f29fdc5b63cedb3289e91de
  6. Affected versionversion=61c3b19f7b9eb7c7838fd35f86566230fefd6550 <bd01629315ffd5b63da91d0bd529a77d30e55028
  7. Affected versionversion=61c3b19f7b9eb7c7838fd35f86566230fefd6550 <c1ba65100a359fe28cfe37e09e10c99f247cbf1e
  8. Affected versionversion=61c3b19f7b9eb7c7838fd35f86566230fefd6550 <ff3357bffd9fb78f59762d8955afc7382a279079

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <8dce4b265a5357731058f69645840dabc718c687; version=2.6.12; version=5.10; version=61c3b19f7b9eb7c7838fd35f86566230fefd6550 <1e501ec38796f43e995731d1bcd4173cb1ccfce0; version=61c3b19f7b9eb7c7838fd35f86566230fefd6550 <82e3a496eb56da0b9f29fdc5b63cedb3289e91de; version=61c3b19f7b9eb7c7838fd35f86566230fefd6550 <bd01629315ffd5b63da91d0bd529a77d30e55028; version=61c3b19f7b9eb7c7838fd35f86566230fefd6550 <c1ba65100a359fe28cfe37e09e10c99f247cbf1e; version=61c3b19f7b9eb7c7838fd35f86566230fefd6550 <ff3357bffd9fb78f59762d8955afc7382a279079

Published CVSS scores

5.5CISA-ADPCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-401Missing Release of Memory after Effective Lifetime
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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