CVE-2021-33034

mediumpriority · track · 41EPSS 0.008 · 57 %ileexploit · PoCDEEURUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

1 exploit · PoC

Likely / severe?

0.83% (57th) EPSS

CVSS 4.6 · medium

Is it mine?

54 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · osv

EPSS · scored 2026-10-27

In the Linux kernel before 5.12.4, net/bluetooth/hci_event.c has a use-after-free when destroying an hci_chan, aka CID-5c4c8c954409. This leads to writing an arbitrary value.

cvss

Technical severity, 0–10. One row per scoring source.

7.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.6–7.8

v2.04.6mediumAV:L/AC:L/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 3.9 · impact 6.4

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 1.8 · impact 5.9

v3.17.8highAV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.17.4highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:Psecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-416USprimaryCWE-416US

exploits (1)

Public proof-of-concept and weaponised exploit code.

Trinadh465/device_renesas_kernel_AOSP10_r33_CVE-2021-33034Trinadh465/device_renesas_kernel_AOSP10_r33_CVE-2021-33034PoC · poc_in_github

affected products (54)

Products and version ranges known to be affected.

Juniper Contrail Service Orchestrationall versionscert_bundDEcpe:/a:juniper:contrail_service_orchestration:-
Juniper Junos Space <21.3R1all versionscert_bundDE
Juniper Junos Space Security Director <24.1R4all versionscert_bundDE
Juniper Junos Space≤ Security Director <24.1R4cert_bundDE
Juniper Junos Space< 21.3R1cert_bundDE
n/a n/a≤ n/aenisa_euvdEU
Canonical Ltd. Ubuntu≤ 20.10fstec_bduRU
Canonical Ltd. Ubuntu≤ 18.04 LTSfstec_bduRU
Canonical Ltd. Ubuntu≤ 20.04 LTSfstec_bduRU
Canonical Ltd. Ubuntu≤ 21.04fstec_bduRU
Canonical Ltd. Ubuntu≤ 14.04 ESMfstec_bduRU
Canonical Ltd. Ubuntu≤ 16.04 ESMfstec_bduRU
Fedora Project Fedora≤ 34fstec_bduRU
Novell Inc. OpenSUSE Leap≤ 15.3fstec_bduRU
Novell Inc. OpenSUSE Leap≤ 15.2fstec_bduRU
Red Hat Inc. Red Hat Enterprise Linux≤ 7.6 Advanced Update Supportfstec_bduRU
Red Hat Inc. Red Hat Enterprise Linux≤ 7.6 Telco Extended Update Supportfstec_bduRU
Red Hat Inc. Red Hat Enterprise Linux≤ 7.6 Update Services for SAP Solutionsfstec_bduRU
Red Hat Inc. Red Hat Enterprise Linux≤ 7.4 Update Services for SAP Solutionsfstec_bduRU
Red Hat Inc. Red Hat Enterprise Linux≤ 8.2 Extended Update Supportfstec_bduRU

showing 20 of 54

advisories (3)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2023-0063Juniper Junos Space: Mehrere SchwachstellenDeutsch2022-01-12csaf · cert_bundDE
Ein Angreifer aus dem angrenzenden Netzwerk oder ein entfernter anonymer, authentisierter oder lokaler Angreifer kann mehrere Schwachstellen in Juniper Junos Space ausnutzen, um Sicherheitsmaßnahmen zu umgehen, vertrauliche Informationen offenzulegen, einen Denial-of-Service-Zustand auszulösen, beliebigen Code auszuführen und seine Privilegien zu erweitern.
WID-SEC-W-2024-1591Juniper JUNOS: Mehrere SchwachstellenDeutsch2024-07-10csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Juniper JUNOS ausnutzen, um einen Denial of Service zu verursachen, Informationen offenzulegen, Privilegien zu erweitern und Sicherheitsmechanismen inklusive zu umgehen.
PUB-A-1946946002022-06-01vendor · osvUS
In hci_send_acl and related functions of hci_core.c, there is a possible way to corrupt memory due to a use after free. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation.

also known as (5)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu osv cert_bund NVD CVE.org MITRE

published 2021-05-14modified 2026-08-13

related (12,251)

Related entries.

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Use after free in Dawn in Google Chrome prior to 146.0.7680.178 allowed a remote attacker who had compromised the renderer process to execute arbitrary code via a crafted HTML page…
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+12246 more

references (54)

External citations — patches, advisories, analysis.

scry

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