Skip to content
Noroxi
NVD / CVE Program· CNA Linux

CVE-2021-47542: net: qlogic: qlcnic: Fix a NULL pointer dereference in qlcnic_83xx_add_rings()

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: 0.25% (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 15fa12c119f869173f9b710cbe6a4a14071d2105, 3a061d54e260b701b538873b43e399d9b8b83e03, 550658a2d61e4eaf522c8ebc7fad76dc376bfb45.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Linux Linux 15fa12c119f869173f9b710cbe6a4a14071d2105, 3a061d54e260b701b538873b43e399d9b8b83e03, 550658a2d61e4eaf522c8ebc7fad76dc376bfb45 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: net: qlogic: qlcnic: Fix a NULL pointer dereference in qlcnic_83xx_add_rings() In qlcnic_83xx_add_rings(), the indirect function of ahw->hw_ops->alloc_mbx_args will be called to allocate memory for cmd.req.arg, and there is a dereference of it in qlcnic_83xx_add_rings(), which could lead to a NULL pointer dereference on failure of the indirect function like qlcnic_83xx_alloc_mbx_args(). Fix this bug by adding a check of alloc_mbx_args(), this patch imitates the logic of mbx_cmd()'s failure handling. This bug was found by a static analyzer. The analysis employs differential checking to identify inconsistent security operations (e.g., checks or kfrees) between two code paths and confirms that the inconsistent operations are not recovered in the current function or the callers, so they constitute bugs. Note that, as a bug found by static analysis, it can be a false positive or hard to trigger. Multiple researchers have cross-reviewed the bug. Builds with CONFIG_QLCNIC=m show no new warnings, and our static analyzer no longer warns about this code.

Published
May 24, 2024
Updated
Jun 17, 2026
EPSS
0.2% · 16th percentile

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.

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.

Follow CVE-2021-47542

When you'll hear from us

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

One daily email digest (06:00 UTC); connect a webhook for KEV listings and weaponized exploits every 10 minutes on paid plans, on the hour on the free plan.

Your free account also gets you

  • CVE alerts: add the products and versions you run, get the new CVEs that affect them
  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools, at most 30 a day (3 a day without an account), an API key and MCP
  • All your scans in one panel: findings, what changed in the last scan, a report per domain or per client (PDF, share link)
All free tools

Sign up with email · Have an account? Sign in

Free account, no card. Unfollow any time.

Don't want an account? Get "Exploited this week" by email every MondayDon't want an account? RSS feed for linux records
Is your version affected? Check it

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.

We use this product, ask for help

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

    • 3.9affected
    • 7f9664525f9cb507de9198a395a111371413f230 and later · before 3a061d54e260b701b538873b43e399d9b8b83e03affected · git
    • 7f9664525f9cb507de9198a395a111371413f230 and later · before b4f217d6fcc00c3fdc0921a7691f30be7490b073affected · git
    • 7f9664525f9cb507de9198a395a111371413f230 and later · before 550658a2d61e4eaf522c8ebc7fad76dc376bfb45affected · git
    • 7f9664525f9cb507de9198a395a111371413f230 and later · before 57af54a56024435d83e44c78449513b414eb6edfaffected · git
    • 7f9664525f9cb507de9198a395a111371413f230 and later · before bbeb0325a7460ebf1e03f5e0bfc5c652fba9519faffected · git
    • 7f9664525f9cb507de9198a395a111371413f230 and later · before 15fa12c119f869173f9b710cbe6a4a14071d2105affected · git
    • 7f9664525f9cb507de9198a395a111371413f230 and later · before c5ef33c1489b2cd74368057fa00b5d2183bb5853affected · git
    • 7f9664525f9cb507de9198a395a111371413f230 and later · before e2dabc4f7e7b60299c20a36d6a7b24ed9bf8e572affected · git
    • before 3.9not affected · semver
Affected versions · NVD (7)

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

  • linux linux kernel3.9 and later · before 4.4.294
  • linux linux kernel4.5 and later · before 4.9.292
  • linux linux kernel4.10 and later · before 4.14.257
  • linux linux kernel4.15 and later · before 4.19.220
  • linux linux kernel4.20 and later · before 5.4.164
  • linux linux kernel5.5 and later · before 5.10.84
  • linux linux kernel5.11 and later · before 5.15.7

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
SUSE:Linux Enterprise High Availability Extension 12 SP5kernel-defaultbefore 4.12.14-122.225.14.12.14-122.225.1
SUSE:Linux Enterprise Live Patching 12 SP5kgraft-patch-SLE12-SP5_Update_59before 1-8.3.11-8.3.1
SUSE:Linux Enterprise Real Time 12 SP5kernel-rtbefore 4.12.14-10.197.14.12.14-10.197.1
SUSE:Linux Enterprise Real Time 12 SP5kernel-rt_debugbefore 4.12.14-10.197.14.12.14-10.197.1
SUSE:Linux Enterprise Real Time 12 SP5kernel-source-rtbefore 4.12.14-10.197.14.12.14-10.197.1
SUSE:Linux Enterprise Real Time 12 SP5kernel-syms-rtbefore 4.12.14-10.197.14.12.14-10.197.1
SUSE:Linux Enterprise Server 12 SP5kernel-sourcebefore 4.12.14-122.225.14.12.14-122.225.1
SUSE:Linux Enterprise Server 12 SP5kernel-symsbefore 4.12.14-122.225.14.12.14-122.225.1
SUSE:Linux Enterprise Software Development Kit 12 SP5kernel-docsbefore 4.12.14-122.225.24.12.14-122.225.2
SUSE:Linux Enterprise Software Development Kit 12 SP5kernel-obs-buildbefore 4.12.14-122.225.14.12.14-122.225.1

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-2021-47540May 24, 2024 · mt76: mt7915: fix NULL pointer dereference in mt7915_get_phy_mode
    22Monitor
  • ← EarlierCVE-2021-47541May 24, 2024 · net/mlx4_en: Fix an use-after-free bug in mlx4_en_try_alloc_resources()
    31Monitor
  • Later →CVE-2021-47544May 24, 2024 · tcp: fix page frag corruption on page fault
    23Monitor

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 Linux15fa12c119f869173f9b710cbe6a4a14071d2105Vendor (CNA)
Linux Linux3a061d54e260b701b538873b43e399d9b8b83e03Vendor (CNA)
Linux Linux550658a2d61e4eaf522c8ebc7fad76dc376bfb45Vendor (CNA)
Linux Linux57af54a56024435d83e44c78449513b414eb6edfVendor (CNA)
Linux Linuxb4f217d6fcc00c3fdc0921a7691f30be7490b073Vendor (CNA)
Linux Linuxbbeb0325a7460ebf1e03f5e0bfc5c652fba9519fVendor (CNA)
Linux Linuxc5ef33c1489b2cd74368057fa00b5d2183bb5853Vendor (CNA)
Linux Linuxe2dabc4f7e7b60299c20a36d6a7b24ed9bf8e572Vendor (CNA)
debian:linux5.15.15-1 · Debian:12Package registry (OSV)
suse:kernel-default4.12.14-122.225.1 · SUSE:Linux Enterprise High Availability Extension 12 SP5Package registry (OSV)
suse:kernel-docs4.12.14-122.225.2 · SUSE:Linux Enterprise Software Development Kit 12 SP5Package registry (OSV)
suse:kernel-obs-build4.12.14-122.225.1 · SUSE:Linux Enterprise Software Development Kit 12 SP5Package registry (OSV)
suse:kernel-rt4.12.14-10.197.1 · SUSE:Linux Enterprise Real Time 12 SP5Package registry (OSV)
suse:kernel-rt_debug4.12.14-10.197.1 · SUSE:Linux Enterprise Real Time 12 SP5Package registry (OSV)
suse:kernel-source4.12.14-122.225.1 · SUSE:Linux Enterprise Server 12 SP5Package registry (OSV)
suse:kernel-source-rt4.12.14-10.197.1 · SUSE:Linux Enterprise Real Time 12 SP5Package registry (OSV)
suse:kernel-syms4.12.14-122.225.1 · SUSE:Linux Enterprise Server 12 SP5Package registry (OSV)
suse:kernel-syms-rt4.12.14-10.197.1 · SUSE:Linux Enterprise Real Time 12 SP5Package registry (OSV)
suse:kgraft-patch-SLE12-SP5_Update_591-8.3.1 · SUSE:Linux Enterprise Live Patching 12 SP5Package 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)

CWE-476 · NULL Pointer Dereference

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 (7 more)

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

All records