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NVD / CVE Program· CNA redhat

CVE-2021-4203: A use-after-free read flaw was found in sock_getsockopt() in net/core/sock.c due to SO_PEERCRED and SO_PEERGROUPS race with listen() (and co

Noroxi assessment

Priority: Monitor (action score 28/100)

  • 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: 1.7% (FIRST EPSS); higher than 77.8% of all records.
  • Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. Special conditions such as timing or configuration are required.
  • Fixed version: linux (Debian:12) 5.14.12-1; dtb-aarch64 (openSUSE:Leap 15.3) 5.3.18-150300.59.93.1; kernel-64kb (openSUSE:Leap 15.3) 5.3.18-150300.59.93.1.
  • Mentioned 3 times in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to linux (Debian:12) 5.14.12-1; dtb-aarch64 (openSUSE:Leap 15.3) 5.3.18-150300.59.93.1; kernel-64kb (openSUSE:Leap 15.3) 5.3.18-150300.59.93.1 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

A use-after-free read flaw was found in sock_getsockopt() in net/core/sock.c due to SO_PEERCRED and SO_PEERGROUPS race with listen() (and connect()) in the Linux kernel. In this flaw, an attacker with a user privileges may crash the system or leak internal kernel information.

MediumCVSS 6.8 · v3.1—No exploit Fix available
Published
Mar 25, 2022
Updated
Jun 17, 2026
EPSS
1.7% · 77th percentile

Report tools

JSON

Action score

28

Monitor

Low priority for now.

CVSS
27 / 40 · 6.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
1 / 30 · 1.7%

Get told when this record changes

  • 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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  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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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
netappactive iq unified manager
netappe-series santricity os controller
netappelement software
netapphci management node
netappsolidfire
netappbootstrap os
netapphci compute node
netappa700s firmware
netappa700s
netapph300s firmware
netapph300s

and 11 more

Affected versions

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

  • linux linux kernelbefore 5.15
  • linux linux kernel5.15
  • netapp a700s firmwareall versions
  • netapp active iq unified managerall versions
  • netapp bootstrap osall versions
  • netapp e-series santricity os controller11.0.0 and later · up to 11.70.2 inclusive
  • netapp element softwareall versions
  • netapp h300s firmwareall versions
  • netapp h410c firmwareall versions
  • netapp h410s firmwareall versions
  • netapp h500s firmwareall versions
  • netapp h700s firmwareall versions
  • netapp hci management nodeall versions
  • netapp solidfireall versions
  • oracle communications cloud native core binding support function22.1.3
  • oracle communications cloud native core network exposure function22.1.1
  • oracle communications cloud native core policy22.2.0

Versions reported by the vendor

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

  • n/a kernel

    • kernel 5.15 rc4affected

Package-level exposure

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

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 5.14.12-15.14.12-1
openSUSE:Leap 15.3dtb-aarch64before 5.3.18-150300.59.93.15.3.18-150300.59.93.1
openSUSE:Leap 15.3kernel-64kbbefore 5.3.18-150300.59.93.15.3.18-150300.59.93.1
openSUSE:Leap 15.3kernel-azurebefore 5.3.18-150300.38.80.15.3.18-150300.38.80.1
openSUSE:Leap 15.3kernel-debugbefore 5.3.18-150300.59.93.15.3.18-150300.59.93.1
openSUSE:Leap 15.3kernel-debugbefore 4.12.14-150100.197.123.14.12.14-150100.197.123.1
openSUSE:Leap 15.3kernel-defaultbefore 4.12.14-150100.197.123.14.12.14-150100.197.123.1
openSUSE:Leap 15.3kernel-docsbefore 5.3.18-150300.59.93.15.3.18-150300.59.93.1
openSUSE:Leap 15.3kernel-kvmsmallbefore 5.3.18-150300.59.93.15.3.18-150300.59.93.1
openSUSE:Leap 15.3kernel-kvmsmallbefore 4.12.14-150100.197.123.14.12.14-150100.197.123.1
openSUSE:Leap 15.3kernel-obs-buildbefore 5.3.18-150300.59.93.15.3.18-150300.59.93.1
openSUSE:Leap 15.3kernel-obs-qabefore 5.3.18-150300.59.93.15.3.18-150300.59.93.1
openSUSE:Leap 15.3kernel-preemptbefore 5.3.18-150300.59.93.15.3.18-150300.59.93.1
openSUSE:Leap 15.3kernel-sourcebefore 5.3.18-150300.59.93.15.3.18-150300.59.93.1
openSUSE:Leap 15.3kernel-source-azurebefore 5.3.18-150300.38.80.15.3.18-150300.38.80.1
openSUSE:Leap 15.3kernel-symsbefore 5.3.18-150300.59.93.15.3.18-150300.59.93.1
openSUSE:Leap 15.3kernel-syms-azurebefore 5.3.18-150300.38.80.15.3.18-150300.38.80.1
openSUSE:Leap 15.3kernel-vanillabefore 4.12.14-150100.197.123.14.12.14-150100.197.123.1
openSUSE:Leap 15.3kernel-zfcpdumpbefore 5.3.18-150300.59.93.15.3.18-150300.59.93.1
openSUSE:Leap 15.3kernel-zfcpdumpbefore 4.12.14-150100.197.123.14.12.14-150100.197.123.1
openSUSE:Leap 15.4kernel-debugbefore 4.12.14-150100.197.137.24.12.14-150100.197.137.2
openSUSE:Leap 15.4kernel-debugbefore 4.12.14-150100.197.142.14.12.14-150100.197.142.1
openSUSE:Leap 15.4kernel-defaultbefore 4.12.14-150100.197.142.14.12.14-150100.197.142.1
openSUSE:Leap 15.4kernel-defaultbefore 4.12.14-150100.197.137.24.12.14-150100.197.137.2

+96

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-2021-4157Mar 25, 2022 · An out of memory bounds write flaw (1 or 2 bytes of memory) in the Linux kernel NFS subsystem was found in the way users use mirroring (repl
    32Monitor
  • ← EarlierCVE-2021-4202Mar 25, 2022 · A use-after-free flaw was found in nci_request in net/nfc/nci/core.c in NFC Controller Interface (NCI) in the Linux kernel.
    28Monitor
  • Later →CVE-2022-0322Mar 25, 2022 · A flaw was found in the sctp_make_strreset_req function in net/sctp/sm_make_chunk.c in the SCTP network protocol in the Linux kernel with a
    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
debian:linux5.14.12-1 · Debian:12Package registry (OSV)
opensuse:dtb-aarch645.3.18-150300.59.93.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-64kb5.3.18-150300.59.93.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-debug5.3.18-150300.59.93.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-default5.3.18-150300.59.93.1 · openSUSE:Leap Micro 5.2Package registry (OSV)
opensuse:kernel-default-base5.3.18-150300.59.93.1.150300.18.54.1 · openSUSE:Leap Micro 5.2Package registry (OSV)
opensuse:kernel-docs5.3.18-150300.59.93.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-kvmsmall5.3.18-150300.59.93.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-obs-build5.3.18-150300.59.93.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-obs-qa5.3.18-150300.59.93.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-preempt5.3.18-150300.59.93.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-source5.3.18-150300.59.93.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-syms5.3.18-150300.59.93.1 · openSUSE:Leap 15.3Package registry (OSV)
red hat:bpftool0:4.18.0-305.57.1.el8_4 · Red Hat:rhel_eus:8.4::baseosPackage registry (OSV)
red hat:bpftool-debuginfo0:4.18.0-305.57.1.el8_4 · Red Hat:rhel_eus:8.4::baseosPackage registry (OSV)
red hat:kernel0:4.18.0-305.57.1.el8_4 · Red Hat:rhel_eus:8.4::baseosPackage registry (OSV)
red hat:kernel-abi-stablelists0:4.18.0-305.57.1.el8_4 · Red Hat:rhel_eus:8.4::baseosPackage registry (OSV)
red hat:kernel-core0:4.18.0-305.57.1.el8_4 · Red Hat:rhel_eus:8.4::baseosPackage registry (OSV)
red hat:kernel-debug0:4.18.0-305.57.1.el8_4 · Red Hat:rhel_eus:8.4::baseosPackage registry (OSV)
red hat:kernel-debug-core0:4.18.0-305.57.1.el8_4 · Red Hat:rhel_eus:8.4::baseosPackage registry (OSV)
red hat:kernel-debug-debuginfo0:4.18.0-305.57.1.el8_4 · Red Hat:rhel_eus:8.4::baseosPackage registry (OSV)
red hat:kernel-debug-devel0:4.18.0-305.57.1.el8_4 · Red Hat:rhel_eus:8.4::baseosPackage registry (OSV)
red hat:kernel-debug-modules0:4.18.0-305.57.1.el8_4 · Red Hat:rhel_eus:8.4::baseosPackage registry (OSV)
red hat:kernel-debug-modules-extra0:4.18.0-305.57.1.el8_4 · Red Hat:rhel_eus:8.4::baseosPackage registry (OSV)
red hat:kernel-debuginfo0:4.18.0-305.57.1.el8_4 · Red Hat:rhel_eus:8.4::baseosPackage registry (OSV)
suse:kernel-64kb5.3.18-150300.59.93.1 · SUSE:Linux Enterprise Module for Basesystem 15 SP3Package registry (OSV)
suse:kernel-default5.3.18-150300.59.93.1 · SUSE:Linux Enterprise Module for Basesystem 15 SP3Package registry (OSV)
suse:kernel-default-base5.3.18-150300.59.93.1.150300.18.54.1 · SUSE:Linux Enterprise Module for Basesystem 15 SP3Package registry (OSV)
suse:kernel-docs5.3.18-150300.59.93.1 · SUSE:Linux Enterprise Module for Development Tools 15 SP3Package registry (OSV)
suse:kernel-livepatch-SLE15-SP3_Update_241-150300.7.3.1 · SUSE:Linux Enterprise Live Patching 15 SP3Package registry (OSV)

+7

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.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

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

All national notices →

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • Special conditions such as timing or configuration are required.

If successful

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

Weakness class (CWE)

CWE-362 · Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

CVSS vector

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

ATT&CK techniques

—

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (4 more)

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

All records