HOMEVULNERABILITIESCVE-2021-3739
HIGH

CVE-2021-3739

CWE-476Published: March 10, 2022· Updated: Jun 17, 2026

7.1
CVSS v3.1

Official Description

A NULL pointer dereference flaw was found in the btrfs_rm_device function in fs/btrfs/volumes.c in the Linux Kernel, where triggering the bug requires ‘CAP_SYS_ADMIN’. This flaw allows a local attacker to crash the system or leak kernel internal information. The highest threat from this vulnerability is to system availability.

NVD Source

Technical Analysis

CVE-2021-3739 requires local access, meaning attackers must already have a foothold on the target system.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A successful exploit results in complete confidentiality breach (data exposure), availability disruption (denial of service), with a CVSS base score of 7.1.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorLocal
Attack ComplexityLow
Privileges Req.Low
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityHigh
IntegrityNone
AvailabilityHigh
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

Affected Vendors & Products

Fedora1 product(s)
fedora
Linux1 product(s)
linux kernel
netapp16 product(s)
h300s firmwareh300sh500s firmwareh500sh700s firmwareh700sh300e firmwareh300eh500e firmwareh500eh700e firmwareh700e+4
Source: NVD CPE · 18 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.

Official Patches & Advisories

PATCHhttps://bugzilla.redhat.com/show_bug.cgi?id=1997958
PATCHhttps://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e4571b8c5e9ffa1e85c0c671995bd4dcc5c75091
PATCHhttps://github.com/torvalds/linux/commit/e4571b8c5e9ffa1e85c0c671995bd4dcc5c75091
PATCHhttps://www.openwall.com/lists/oss-security/2021/08/25/3
PATCHhttps://bugzilla.redhat.com/show_bug.cgi?id=1997958
PATCHhttps://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e4571b8c5e9ffa1e85c0c671995bd4dcc5c75091
PATCHhttps://github.com/torvalds/linux/commit/e4571b8c5e9ffa1e85c0c671995bd4dcc5c75091
PATCHhttps://www.openwall.com/lists/oss-security/2021/08/25/3
ADVISORYhttps://security.netapp.com/advisory/ntap-20220407-0006/
ADVISORYhttps://ubuntu.com/security/CVE-2021-3739
ADVISORYhttps://security.netapp.com/advisory/ntap-20220407-0006/
ADVISORYhttps://ubuntu.com/security/CVE-2021-3739

All References (12)

→
https://bugzilla.redhat.com/show_bug.cgi?id=1997958Issue Tracking · Patch · Third Party Advisory
→
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e4571b8c5e9ffa1e85c0c671995bd4dcc5c75091Mailing List · Patch · Vendor Advisory
→
https://github.com/torvalds/linux/commit/e4571b8c5e9ffa1e85c0c671995bd4dcc5c75091Exploit · Patch · Third Party Advisory
→
https://security.netapp.com/advisory/ntap-20220407-0006/Third Party Advisory
→
https://ubuntu.com/security/CVE-2021-3739Third Party Advisory
→
https://www.openwall.com/lists/oss-security/2021/08/25/3Mailing List · Patch · Third Party Advisory
→
https://bugzilla.redhat.com/show_bug.cgi?id=1997958Issue Tracking · Patch · Third Party Advisory
→
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e4571b8c5e9ffa1e85c0c671995bd4dcc5c75091Mailing List · Patch · Vendor Advisory
→
https://github.com/torvalds/linux/commit/e4571b8c5e9ffa1e85c0c671995bd4dcc5c75091Exploit · Patch · Third Party Advisory
→
https://security.netapp.com/advisory/ntap-20220407-0006/Third Party Advisory
→
https://ubuntu.com/security/CVE-2021-3739Third Party Advisory
→
https://www.openwall.com/lists/oss-security/2021/08/25/3Mailing List · Patch · Third Party Advisory

Quick Facts

CVE IDCVE-2021-3739
CVSS Score7.1 / 10
SeverityHIGH
WeaknessCWE-476
CISA KEVNo
Affected3 vendor(s)
PublishedMar 10, 2022

Related CVEs (CWE-476)

CVE-2022-36648
10.0
CVE-2010-2495
10.0
CVE-2021-1946
9.8
CVE-2019-17539
9.8
CVE-2019-20914
9.8
CVE-2019-16092
9.8

Recommended Actions

  • →Apply vendor patches immediately
  • →Monitor CVE-2021-3739 in threat intel feeds
  • →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWatch. CVE data is provided under the NVD usage policy.
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