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NVD / CVE Program· CNA redhat

CVE-2021-3923: A flaw was found in the Linux kernel's implementation of RDMA over infiniband.

Noroxi assessment

Priority: Monitor (action score 9/100)

  • 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: 0.19% (FIRST EPSS).
  • Someone with local access to the system can trigger it. Administrator privileges are required. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: CBL Mariner 1.0 ARM 5.10.177.1-1; CBL Mariner 1.0 x64 5.10.177.1-1.

Low priority for now. Upgrade to CBL Mariner 1.0 ARM 5.10.177.1-1; CBL Mariner 1.0 x64 5.10.177.1-1 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 flaw was found in the Linux kernel's implementation of RDMA over infiniband. An attacker with a privileged local account can leak kernel stack information when issuing commands to the /dev/infiniband/rdma_cm device node. While this access is unlikely to leak sensitive user information, it can be further used to defeat existing kernel protection mechanisms.

LowCVSS 2.3 · v3.1—No exploit Fix available
Published
Mar 27, 2023
Updated
Jun 17, 2026
EPSS
0.1% · 9th percentile

Report tools

JSON

Action score

9

Monitor

Low priority for now.

CVSS
9 / 40 · 2.3 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.1%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

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

If any of these changes, we'll tell you in the daily email digest.

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When you'll hear from us

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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
redhatenterprise linux
fedoraprojectfedora

Affected versions

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

  • fedoraproject fedora37
  • linux linux kernelbefore 5.15.14
  • redhat enterprise linux6.0
  • redhat enterprise linux7.0
  • redhat enterprise linux8.0

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

    • unknownaffected

Package-level exposure

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

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 5.15.15-15.15.15-1
openSUSE:Leap 15.4dtb-aarch64before 5.3.18-150300.59.118.15.3.18-150300.59.118.1
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-kvmsmallbefore 4.12.14-150100.197.142.14.12.14-150100.197.142.1
openSUSE:Leap 15.4kernel-vanillabefore 4.12.14-150100.197.142.14.12.14-150100.197.142.1
openSUSE:Leap 15.4kernel-zfcpdumpbefore 4.12.14-150100.197.142.14.12.14-150100.197.142.1
Red Hat:enterprise_linux:8::baseosbpftoolbefore 0:4.18.0-372.9.1.el80:4.18.0-372.9.1.el8
Red Hat:enterprise_linux:8::baseosbpftool-debuginfobefore 0:4.18.0-372.9.1.el80:4.18.0-372.9.1.el8
Red Hat:enterprise_linux:8::baseoskernelbefore 0:4.18.0-372.9.1.el80:4.18.0-372.9.1.el8
Red Hat:enterprise_linux:8::baseoskernel-abi-stablelistsbefore 0:4.18.0-372.9.1.el80:4.18.0-372.9.1.el8
Red Hat:enterprise_linux:8::baseoskernel-corebefore 0:4.18.0-372.9.1.el80:4.18.0-372.9.1.el8
Red Hat:enterprise_linux:8::baseoskernel-debugbefore 0:4.18.0-372.9.1.el80:4.18.0-372.9.1.el8
Red Hat:enterprise_linux:8::baseoskernel-debug-corebefore 0:4.18.0-372.9.1.el80:4.18.0-372.9.1.el8
Red Hat:enterprise_linux:8::baseoskernel-debug-debuginfobefore 0:4.18.0-372.9.1.el80:4.18.0-372.9.1.el8
Red Hat:enterprise_linux:8::baseoskernel-debug-develbefore 0:4.18.0-372.9.1.el80:4.18.0-372.9.1.el8
Red Hat:enterprise_linux:8::baseoskernel-debug-modulesbefore 0:4.18.0-372.9.1.el80:4.18.0-372.9.1.el8
Red Hat:enterprise_linux:8::baseoskernel-debug-modules-extrabefore 0:4.18.0-372.9.1.el80:4.18.0-372.9.1.el8
Red Hat:enterprise_linux:8::baseoskernel-debuginfobefore 0:4.18.0-372.9.1.el80:4.18.0-372.9.1.el8
Red Hat:enterprise_linux:8::baseoskernel-debuginfo-common-aarch64before 0:4.18.0-372.9.1.el80:4.18.0-372.9.1.el8
Red Hat:enterprise_linux:8::baseoskernel-debuginfo-common-ppc64lebefore 0:4.18.0-372.9.1.el80:4.18.0-372.9.1.el8
Red Hat:enterprise_linux:8::baseoskernel-debuginfo-common-s390xbefore 0:4.18.0-372.9.1.el80:4.18.0-372.9.1.el8
Red Hat:enterprise_linux:8::baseoskernel-debuginfo-common-x86_64before 0:4.18.0-372.9.1.el80:4.18.0-372.9.1.el8
Red Hat:enterprise_linux:8::baseoskernel-develbefore 0:4.18.0-372.9.1.el80:4.18.0-372.9.1.el8

+79

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-2023-1583Mar 24, 2023 · A NULL pointer dereference was found in io_file_bitmap_get in io_uring/filetable.c in the io_uring sub-component in the Linux Kernel.
    22Monitor
  • ← EarlierCVE-2023-28866Mar 26, 2023 · In the Linux kernel through 6.2.8, net/bluetooth/hci_sync.c allows out-of-bounds access because amp_init1[] and amp_init2[] are supposed to
    21Monitor
  • Later →CVE-2023-1073Mar 27, 2023 · A memory corruption flaw was found in the Linux kernel’s human interface device (HID) subsystem in how a user inserts a malicious USB device
    26Monitor

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
CBL Mariner 1.0 ARM5.10.177.1-1 · kernelMicrosoft (MSRC)
CBL Mariner 1.0 x645.10.177.1-1 · kernelMicrosoft (MSRC)
debian:linux5.15.15-1 · Debian:12Package registry (OSV)
opensuse:dtb-aarch645.3.18-150300.59.118.1 · openSUSE:Leap 15.4Package registry (OSV)
opensuse:kernel-debug4.12.14-150100.197.142.1 · openSUSE:Leap 15.4Package registry (OSV)
opensuse:kernel-default4.12.14-150100.197.142.1 · openSUSE:Leap 15.4Package registry (OSV)
opensuse:kernel-kvmsmall4.12.14-150100.197.142.1 · openSUSE:Leap 15.4Package registry (OSV)
opensuse:kernel-vanilla4.12.14-150100.197.142.1 · openSUSE:Leap 15.4Package registry (OSV)
opensuse:kernel-zfcpdump4.12.14-150100.197.142.1 · openSUSE:Leap 15.4Package registry (OSV)
red hat:kernel-rt0:4.18.0-372.9.1.rt7.166.el8 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-core0:4.18.0-372.9.1.rt7.166.el8 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debug0:4.18.0-372.9.1.rt7.166.el8 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debug-core0:4.18.0-372.9.1.rt7.166.el8 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debug-debuginfo0:4.18.0-372.9.1.rt7.166.el8 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debug-devel0:4.18.0-372.9.1.rt7.166.el8 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debug-kvm0:4.18.0-372.9.1.rt7.166.el8 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debug-modules0:4.18.0-372.9.1.rt7.166.el8 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debug-modules-extra0:4.18.0-372.9.1.rt7.166.el8 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debuginfo0:4.18.0-372.9.1.rt7.166.el8 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debuginfo-common-x86_640:4.18.0-372.9.1.rt7.166.el8 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-devel0:4.18.0-372.9.1.rt7.166.el8 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
suse:kernel-64kb5.3.18-150300.59.118.1 · SUSE:Linux Enterprise High Performance Computing 15 SP3-ESPOSPackage registry (OSV)
suse:kernel-azure4.12.14-16.130.1 · SUSE:Linux Enterprise Server 12 SP5Package registry (OSV)
suse:kernel-default5.3.18-150200.24.148.1 · SUSE:Linux Enterprise Live Patching 15 SP2Package registry (OSV)
suse:kernel-default5.3.18-150300.59.118.1 · SUSE:Linux Enterprise Live Patching 15 SP3Package registry (OSV)
suse:kernel-default-base5.3.18-150200.24.148.1.150200.9.71.1 · SUSE:Linux Enterprise High Performance Computing 15 SP2-LTSSPackage registry (OSV)
suse:kernel-default-base5.3.18-150300.59.118.1.150300.18.68.1 · SUSE:Linux Enterprise High Performance Computing 15 SP3-ESPOSPackage registry (OSV)
suse:kernel-docs5.3.18-150200.24.148.1 · SUSE:Linux Enterprise High Performance Computing 15 SP2-LTSSPackage registry (OSV)
suse:kernel-docs5.3.18-150300.59.118.1 · SUSE:Linux Enterprise High Performance Computing 15 SP3-ESPOSPackage registry (OSV)
suse:kernel-livepatch-SLE15-SP1_Update_391-150100.3.5.1 · SUSE:Linux Enterprise Live Patching 15 SP1Package registry (OSV)

+14

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.

No commit or PR link among the references.

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).

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • Administrator privileges are required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
low · data can be read
Integrity
none
Availability
none
Attack vector
Local
Attack complexity
Low
Privileges required
High
User interaction
None
Scope
Unchanged
Confidentiality impact
Low
Integrity impact
None
Availability impact
None

Weakness class (CWE)

CWE-200 · Exposure of Sensitive Information to an Unauthorized Actor

CVSS vector

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

nvd-primary

Root cause

The extension requests broader permissions than its function needs and sends the data it collects out for purposes beyond its stated function.

The bug in code

The whole CWE-200 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

json
{  "permissions": ["tabs", "<all_urls>"],  "background": { "service_worker": "analytics.js" }}

Fixed

json
{  "permissions": ["activeTab"],  "host_permissions": ["https://yildiz.example/*"]}

Attack context

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

Change log

  1. Fix✗ → ✓

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

References

Show all references (1 more)

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

All records