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NVD / CVE Program· CNA Linux

CVE-2021-46974: bpf: Fix masking negation logic upon negative dst register

MediumCVSS 5.5 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 22/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.24% (FIRST EPSS).
  • Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Linux Linux 0e2dfdc74a7f4036127356d42ea59388f153f42c, 2cfa537674cd1051a3b8111536d77d0558f33d5d, 4.14.233.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Linux Linux 0e2dfdc74a7f4036127356d42ea59388f153f42c, 2cfa537674cd1051a3b8111536d77d0558f33d5d, 4.14.233 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix masking negation logic upon negative dst register The negation logic for the case where the off_reg is sitting in the dst register is not correct given then we cannot just invert the add to a sub or vice versa. As a fix, perform the final bitwise and-op unconditionally into AX from the off_reg, then move the pointer from the src to dst and finally use AX as the source for the original pointer arithmetic operation such that the inversion yields a correct result. The single non-AX mov in between is possible given constant blinding is retaining it as it's not an immediate based operation.

Published
Feb 27, 2024
Updated
Aug 5, 2026
EPSS
0.2% · 16th percentile
CWE
—

Report tools

JSON

Action score

22

Monitor

Low priority for now.

CVSS
22 / 40 · 5.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.2%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
5.5
CNA · Linux
7.1
1.6 point gap

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

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  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

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Follow CVE-2021-46974

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
linuxlinux kernel

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

  • Linux Linux

    • 078da99d449f64ca04d459cdbdcce513b64173cd, 5.0affected
    • ae03b6b1c880a03d4771257336dc3bca156dd51b and later · before 4d542ddb88fb2f39bf7f14caa2902f3e8d06f6baaffected · git
    • f92a819b4cbef8c9527d9797110544b2055a4b96 and later · before 0e2dfdc74a7f4036127356d42ea59388f153f42caffected · git
    • 979d63d50c0c0f7bc537bf821e056cc9fe5abd38 and later · before 53e0db429b37a32b8fc706d0d90eb4583ad13848affected · git
    • 979d63d50c0c0f7bc537bf821e056cc9fe5abd38 and later · before 2cfa537674cd1051a3b8111536d77d0558f33d5daffected · git
    • 979d63d50c0c0f7bc537bf821e056cc9fe5abd38 and later · before 6eba92a4d4be8feb4dc33976abac544fa99d6eccaffected · git
    • 979d63d50c0c0f7bc537bf821e056cc9fe5abd38 and later · before 7cf64d8679ca1cb20cf57d6a88bfee79a0922a66affected · git
    • 979d63d50c0c0f7bc537bf821e056cc9fe5abd38 and later · before b9b34ddbe2076ade359cd5ce7537d5ed019e9807affected · git
    • 4.14.113 and later · before 4.14.233affected · semver
    • 4.19.19 and later · before 4.19.190affected · semver
Affected versions · NVD (6)

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • linux linux kernel4.14.113 and later · before 4.14.233
  • linux linux kernel4.19.19 and later · before 4.19.190
  • linux linux kernel5.0 and later · before 5.4.117
  • linux linux kernel5.5 and later · before 5.10.35
  • linux linux kernel5.11 and later · before 5.11.19
  • linux linux kernel5.12 and later · before 5.12.2

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 5.10.38-15.10.38-1
SUSE:Linux Enterprise High Availability Extension 12 SP5kernel-defaultbefore 4.12.14-122.201.14.12.14-122.201.1
SUSE:Linux Enterprise High Performance Computing 15 SP2-LTSSkernel-default-basebefore 5.3.18-150200.24.183.1.150200.9.93.25.3.18-150200.24.183.1.150200.9.93.2
SUSE:Linux Enterprise High Performance Computing 15 SP2-LTSSkernel-docsbefore 5.3.18-150200.24.183.15.3.18-150200.24.183.1
SUSE:Linux Enterprise High Performance Computing 15 SP2-LTSSkernel-obs-buildbefore 5.3.18-150200.24.183.15.3.18-150200.24.183.1
SUSE:Linux Enterprise High Performance Computing 15 SP2-LTSSkernel-preemptbefore 5.3.18-150200.24.183.15.3.18-150200.24.183.1
SUSE:Linux Enterprise High Performance Computing 15 SP2-LTSSkernel-sourcebefore 5.3.18-150200.24.183.15.3.18-150200.24.183.1
SUSE:Linux Enterprise High Performance Computing 15 SP2-LTSSkernel-symsbefore 5.3.18-150200.24.183.15.3.18-150200.24.183.1
SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSSkernel-64kbbefore 5.3.18-150300.59.153.25.3.18-150300.59.153.2
SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSSkernel-default-basebefore 5.3.18-150300.59.153.2.150300.18.90.25.3.18-150300.59.153.2.150300.18.90.2
SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSSkernel-docsbefore 5.3.18-150300.59.153.25.3.18-150300.59.153.2
SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSSkernel-obs-buildbefore 5.3.18-150300.59.153.25.3.18-150300.59.153.2
SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSSkernel-preemptbefore 5.3.18-150300.59.153.25.3.18-150300.59.153.2
SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSSkernel-sourcebefore 5.3.18-150300.59.153.25.3.18-150300.59.153.2
SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSSkernel-symsbefore 5.3.18-150300.59.153.15.3.18-150300.59.153.1
SUSE:Linux Enterprise Live Patching 12 SP5kgraft-patch-SLE12-SP5_Update_54before 1-8.7.11-8.7.1
SUSE:Linux Enterprise Live Patching 15 SP2kernel-defaultbefore 5.3.18-150200.24.183.15.3.18-150200.24.183.1
SUSE:Linux Enterprise Live Patching 15 SP2kernel-livepatch-SLE15-SP2_Update_46before 1-150200.5.3.21-150200.5.3.2
SUSE:Linux Enterprise Live Patching 15 SP3kernel-defaultbefore 5.3.18-150300.59.153.25.3.18-150300.59.153.2
SUSE:Linux Enterprise Live Patching 15 SP3kernel-livepatch-SLE15-SP3_Update_42before 1-150300.7.3.21-150300.7.3.2
SUSE:Linux Enterprise Micro 5.1kernel-rtbefore 5.3.18-150300.161.15.3.18-150300.161.1
SUSE:Linux Enterprise Micro 5.1kernel-source-rtbefore 5.3.18-150300.161.15.3.18-150300.161.1
SUSE:Linux Enterprise Real Time 12 SP5kernel-rtbefore 4.12.14-10.171.14.12.14-10.171.1
SUSE:Linux Enterprise Real Time 12 SP5kernel-rt_debugbefore 4.12.14-10.171.14.12.14-10.171.1

+10

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
    90Now
  • CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe…KEV
    89Now
  • CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
    85Now

Published before and after this one in the same product

  • ← EarlierCVE-2021-46972Feb 27, 2024 · ovl: fix leaked dentry
    22Monitor
  • ← EarlierCVE-2021-46973Feb 27, 2024 · net: qrtr: Avoid potential use after free in MHI send
    31Monitor
  • Later →CVE-2020-36778Feb 28, 2024 · i2c: xiic: fix reference leak when pm_runtime_get_sync fails
    22Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Linux Linux0e2dfdc74a7f4036127356d42ea59388f153f42cVendor (CNA)
Linux Linux2cfa537674cd1051a3b8111536d77d0558f33d5dVendor (CNA)
Linux Linux4.14.233Vendor (CNA)
Linux Linux4.19.190Vendor (CNA)
Linux Linux4.21Vendor (CNA)
Linux Linux4d542ddb88fb2f39bf7f14caa2902f3e8d06f6baVendor (CNA)
Linux Linux53e0db429b37a32b8fc706d0d90eb4583ad13848Vendor (CNA)
Linux Linux6eba92a4d4be8feb4dc33976abac544fa99d6eccVendor (CNA)
Linux Linux7cf64d8679ca1cb20cf57d6a88bfee79a0922a66Vendor (CNA)
Linux Linuxb9b34ddbe2076ade359cd5ce7537d5ed019e9807Vendor (CNA)
debian:linux5.10.38-1 · Debian:12Package registry (OSV)
suse:kernel-64kb5.3.18-150300.59.153.2 · SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSSPackage registry (OSV)
suse:kernel-default5.3.18-150300.59.153.2 · SUSE:Linux Enterprise Live Patching 15 SP3Package registry (OSV)
suse:kernel-default-base5.3.18-150300.59.153.2.150300.18.90.2 · SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSSPackage registry (OSV)
suse:kernel-docs5.3.18-150300.59.153.2 · SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSSPackage registry (OSV)
suse:kernel-livepatch-SLE15-SP3_Update_421-150300.7.3.2 · SUSE:Linux Enterprise Live Patching 15 SP3Package registry (OSV)
suse:kernel-obs-build5.3.18-150300.59.153.2 · SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSSPackage registry (OSV)
suse:kernel-preempt5.3.18-150300.59.153.2 · SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSSPackage registry (OSV)
suse:kernel-rt5.3.18-150300.161.1 · SUSE:Linux Enterprise Micro 5.1Package registry (OSV)
suse:kernel-source5.3.18-150300.59.153.2 · SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSSPackage registry (OSV)
suse:kernel-source-rt5.3.18-150300.161.1 · SUSE:Linux Enterprise Micro 5.1Package registry (OSV)
suse:kernel-syms5.3.18-150300.59.153.1 · SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSSPackage registry (OSV)
suse:kernel-zfcpdump5.3.18-150300.59.153.2 · SUSE:Linux Enterprise Server 15 SP3-LTSSPackage registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

Not on record for this CVE: EPSS history · patch commit or PR link · researcher credit · variant or chain candidate · public bounty program.

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

—

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

References

Show all references (6 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records