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NVD / CVE Program· CNA Linux

CVE-2021-47284: isdn: mISDN: netjet: Fix crash in nj_probe:

Noroxi assessment

Priority: Monitor (action score 18/100)

  • 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: 0.22% (FIRST EPSS).
  • Someone with local access to the system 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 Linux 143fc7220961220eecc04669e5909af8847bf8c8, 4c1fcb6ec964b44edbf84235134582a5ffae1521, 6249193e03709ea625e10706ecaf17fea0427d3d.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Linux Linux 143fc7220961220eecc04669e5909af8847bf8c8, 4c1fcb6ec964b44edbf84235134582a5ffae1521, 6249193e03709ea625e10706ecaf17fea0427d3d 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: isdn: mISDN: netjet: Fix crash in nj_probe: 'nj_setup' in netjet.c might fail with -EIO and in this case 'card->irq' is initialized and is bigger than zero. A subsequent call to 'nj_release' will free the irq that has not been requested. Fix this bug by deleting the previous assignment to 'card->irq' and just keep the assignment before 'request_irq'. The KASAN's log reveals it: [ 3.354615 ] WARNING: CPU: 0 PID: 1 at kernel/irq/manage.c:1826 free_irq+0x100/0x480 [ 3.355112 ] Modules linked in: [ 3.355310 ] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.13.0-rc1-00144-g25a1298726e #13 [ 3.355816 ] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 [ 3.356552 ] RIP: 0010:free_irq+0x100/0x480 [ 3.356820 ] Code: 6e 08 74 6f 4d 89 f4 e8 5e ac 09 00 4d 8b 74 24 18 4d 85 f6 75 e3 e8 4f ac 09 00 8b 75 c8 48 c7 c7 78 c1 2e 85 e8 e0 cf f5 ff <0f> 0b 48 8b 75 c0 4c 89 ff e8 72 33 0b 03 48 8b 43 40 4c 8b a0 80 [ 3.358012 ] RSP: 0000:ffffc90000017b48 EFLAGS: 00010082 [ 3.358357 ] RAX: 0000000000000000 RBX: ffff888104dc8000 RCX: 0000000000000000 [ 3.358814 ] RDX: ffff8881003c8000 RSI: ffffffff8124a9e6 RDI: 00000000ffffffff [ 3.359272 ] RBP: ffffc90000017b88 R08: 0000000000000000 R09: 0000000000000000 [ 3.359732 ] R10: ffffc900000179f0 R11: 0000000000001d04 R12: 0000000000000000 [ 3.360195 ] R13: ffff888107dc6000 R14: ffff888107dc6928 R15: ffff888104dc80a8 [ 3.360652 ] FS: 0000000000000000(0000) GS:ffff88817bc00000(0000) knlGS:0000000000000000 [ 3.361170 ] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3.361538 ] CR2: 0000000000000000 CR3: 000000000582e000 CR4: 00000000000006f0 [ 3.362003 ] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 3.362175 ] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 3.362175 ] Call Trace: [ 3.362175 ] nj_release+0x51/0x1e0 [ 3.362175 ] nj_probe+0x450/0x950 [ 3.362175 ] ? pci_device_remove+0x110/0x110 [ 3.362175 ] local_pci_probe+0x45/0xa0 [ 3.362175 ] pci_device_probe+0x12b/0x1d0 [ 3.362175 ] really_probe+0x2a9/0x610 [ 3.362175 ] driver_probe_device+0x90/0x1d0 [ 3.362175 ] ? mutex_lock_nested+0x1b/0x20 [ 3.362175 ] device_driver_attach+0x68/0x70 [ 3.362175 ] __driver_attach+0x124/0x1b0 [ 3.362175 ] ? device_driver_attach+0x70/0x70 [ 3.362175 ] bus_for_each_dev+0xbb/0x110 [ 3.362175 ] ? rdinit_setup+0x45/0x45 [ 3.362175 ] driver_attach+0x27/0x30 [ 3.362175 ] bus_add_driver+0x1eb/0x2a0 [ 3.362175 ] driver_register+0xa9/0x180 [ 3.362175 ] __pci_register_driver+0x82/0x90 [ 3.362175 ] ? w6692_init+0x38/0x38 [ 3.362175 ] nj_init+0x36/0x38 [ 3.362175 ] do_one_initcall+0x7f/0x3d0 [ 3.362175 ] ? rdinit_setup+0x45/0x45 [ 3.362175 ] ? rcu_read_lock_sched_held+0x4f/0x80 [ 3.362175 ] kernel_init_freeable+0x2aa/0x301 [ 3.362175 ] ? rest_init+0x2c0/0x2c0 [ 3.362175 ] kernel_init+0x18/0x190 [ 3.362175 ] ? rest_init+0x2c0/0x2c0 [ 3.362175 ] ? rest_init+0x2c0/0x2c0 [ 3.362175 ] ret_from_fork+0x1f/0x30 [ 3.362175 ] Kernel panic - not syncing: panic_on_warn set ... [ 3.362175 ] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.13.0-rc1-00144-g25a1298726e #13 [ 3.362175 ] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 [ 3.362175 ] Call Trace: [ 3.362175 ] dump_stack+0xba/0xf5 [ 3.362175 ] ? free_irq+0x100/0x480 [ 3.362175 ] panic+0x15a/0x3f2 [ 3.362175 ] ? __warn+0xf2/0x150 [ 3.362175 ] ? free_irq+0x100/0x480 [ 3.362175 ] __warn+0x108/0x150 [ 3.362175 ] ? free_irq+0x100/0x480 [ 3.362175 ] report_bug+0x119/0x1c0 [ 3.362175 ] handle_bug+0x3b/0x80 [ 3.362175 ] exc_invalid_op+0x18/0x70 [ 3.362175 ] asm_exc_invalid_op+0x12/0x20 [ 3.362175 ] RIP: 0010:free_irq+0x100 ---truncated---

MediumCVSS 4.7 · v3.1—No exploit Fix available
Published
May 21, 2024
Updated
Jun 17, 2026
EPSS
0.2% · 13th percentile

Report tools

JSON

Action score

18

Monitor

Low priority for now.

CVSS
18 / 40 · 4.7 / 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

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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

Affected versions

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

  • linux linux kernelbefore 4.4.273
  • linux linux kernel4.5 and later · before 4.9.273
  • linux linux kernel4.10 and later · before 4.14.237
  • linux linux kernel4.15 and later · before 4.19.195
  • linux linux kernel4.20 and later · before 5.4.126
  • linux linux kernel5.5 and later · before 5.10.44
  • linux linux kernel5.11 and later · before 5.12.11
  • linux linux kernel5.13

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

    • 2.6.32affected
    • a900845e56617edc005fd8f35bfd5a407aaf96c8 and later · before 958cb1078ca60d214826fd90a0961a447fade59aaffected · git
    • a900845e56617edc005fd8f35bfd5a407aaf96c8 and later · before 4c1fcb6ec964b44edbf84235134582a5ffae1521affected · git
    • a900845e56617edc005fd8f35bfd5a407aaf96c8 and later · before a0a37e4454ca1c0b424edc2c9c2487c2c46a1be6affected · git
    • a900845e56617edc005fd8f35bfd5a407aaf96c8 and later · before bf78e25bd3f487208e042c67c8a31706c2dba265affected · git
    • a900845e56617edc005fd8f35bfd5a407aaf96c8 and later · before 9d7d4649dc1c53acf76df260fd519db698ed20d7affected · git
    • a900845e56617edc005fd8f35bfd5a407aaf96c8 and later · before 143fc7220961220eecc04669e5909af8847bf8c8affected · git
    • a900845e56617edc005fd8f35bfd5a407aaf96c8 and later · before 6249193e03709ea625e10706ecaf17fea0427d3daffected · git
    • a900845e56617edc005fd8f35bfd5a407aaf96c8 and later · before 9f6f852550d0e1b7735651228116ae9d300f69b3affected · git
    • before 2.6.32not affected · semver

Package-level exposure

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

EcosystemPackageAffected rangeFix
AlmaLinux:8bpftoolbefore 4.18.0-553.16.1.el8_104.18.0-553.16.1.el8_10
AlmaLinux:8kernelbefore 4.18.0-553.16.1.el8_104.18.0-553.16.1.el8_10
AlmaLinux:8kernel-abi-stablelistsbefore 4.18.0-553.16.1.el8_104.18.0-553.16.1.el8_10
AlmaLinux:8kernel-corebefore 4.18.0-553.16.1.el8_104.18.0-553.16.1.el8_10
AlmaLinux:8kernel-cross-headersbefore 4.18.0-553.16.1.el8_104.18.0-553.16.1.el8_10
AlmaLinux:8kernel-debugbefore 4.18.0-553.16.1.el8_104.18.0-553.16.1.el8_10
AlmaLinux:8kernel-debug-corebefore 4.18.0-553.16.1.el8_104.18.0-553.16.1.el8_10
AlmaLinux:8kernel-debug-develbefore 4.18.0-553.16.1.el8_104.18.0-553.16.1.el8_10
AlmaLinux:8kernel-debug-modulesbefore 4.18.0-553.16.1.el8_104.18.0-553.16.1.el8_10
AlmaLinux:8kernel-debug-modules-extrabefore 4.18.0-553.16.1.el8_104.18.0-553.16.1.el8_10
AlmaLinux:8kernel-develbefore 4.18.0-553.16.1.el8_104.18.0-553.16.1.el8_10
AlmaLinux:8kernel-docbefore 4.18.0-553.16.1.el8_104.18.0-553.16.1.el8_10
AlmaLinux:8kernel-headersbefore 4.18.0-553.16.1.el8_104.18.0-553.16.1.el8_10
AlmaLinux:8kernel-modulesbefore 4.18.0-553.16.1.el8_104.18.0-553.16.1.el8_10
AlmaLinux:8kernel-modules-extrabefore 4.18.0-553.16.1.el8_104.18.0-553.16.1.el8_10
AlmaLinux:8kernel-rtbefore 4.18.0-553.16.1.rt7.357.el8_104.18.0-553.16.1.rt7.357.el8_10
AlmaLinux:8kernel-rt-corebefore 4.18.0-553.16.1.rt7.357.el8_104.18.0-553.16.1.rt7.357.el8_10
AlmaLinux:8kernel-rt-debugbefore 4.18.0-553.16.1.rt7.357.el8_104.18.0-553.16.1.rt7.357.el8_10
AlmaLinux:8kernel-rt-debug-corebefore 4.18.0-553.16.1.rt7.357.el8_104.18.0-553.16.1.rt7.357.el8_10
AlmaLinux:8kernel-rt-debug-develbefore 4.18.0-553.16.1.rt7.357.el8_104.18.0-553.16.1.rt7.357.el8_10
AlmaLinux:8kernel-rt-debug-kvmbefore 4.18.0-553.16.1.rt7.357.el8_104.18.0-553.16.1.rt7.357.el8_10
AlmaLinux:8kernel-rt-debug-modulesbefore 4.18.0-553.16.1.rt7.357.el8_104.18.0-553.16.1.rt7.357.el8_10
AlmaLinux:8kernel-rt-debug-modules-extrabefore 4.18.0-553.16.1.rt7.357.el8_104.18.0-553.16.1.rt7.357.el8_10
AlmaLinux:8kernel-rt-develbefore 4.18.0-553.16.1.rt7.357.el8_104.18.0-553.16.1.rt7.357.el8_10

+66

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-2021-47282May 21, 2024 · spi: bcm2835: Fix out-of-bounds access with more than 4 slaves
    31Monitor
  • ← EarlierCVE-2021-47283May 21, 2024 · net:sfc: fix non-freed irq in legacy irq mode
    22Monitor
  • Later →CVE-2021-47286May 21, 2024 · bus: mhi: core: Validate channel ID when processing command completions
    31Monitor

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 Linux143fc7220961220eecc04669e5909af8847bf8c8Vendor (CNA)
Linux Linux4c1fcb6ec964b44edbf84235134582a5ffae1521Vendor (CNA)
Linux Linux6249193e03709ea625e10706ecaf17fea0427d3dVendor (CNA)
Linux Linux958cb1078ca60d214826fd90a0961a447fade59aVendor (CNA)
Linux Linux9d7d4649dc1c53acf76df260fd519db698ed20d7Vendor (CNA)
Linux Linux9f6f852550d0e1b7735651228116ae9d300f69b3Vendor (CNA)
Linux Linuxa0a37e4454ca1c0b424edc2c9c2487c2c46a1be6Vendor (CNA)
Linux Linuxbf78e25bd3f487208e042c67c8a31706c2dba265Vendor (CNA)
almalinux:bpftool4.18.0-553.16.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel4.18.0-553.16.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-abi-stablelists4.18.0-553.16.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-core4.18.0-553.16.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-cross-headers4.18.0-553.16.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-debug4.18.0-553.16.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-debug-core4.18.0-553.16.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-debug-devel4.18.0-553.16.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-debug-modules4.18.0-553.16.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-debug-modules-extra4.18.0-553.16.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-devel4.18.0-553.16.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-doc4.18.0-553.16.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt4.18.0-553.16.1.rt7.357.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-core4.18.0-553.16.1.rt7.357.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug4.18.0-553.16.1.rt7.357.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-core4.18.0-553.16.1.rt7.357.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-devel4.18.0-553.16.1.rt7.357.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-kvm4.18.0-553.16.1.rt7.357.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-modules4.18.0-553.16.1.rt7.357.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-modules-extra4.18.0-553.16.1.rt7.357.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-devel4.18.0-553.16.1.rt7.357.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-kvm4.18.0-553.16.1.rt7.357.el8_10 · AlmaLinux:8Package registry (OSV)

+17

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.

  • CVE-2024-3946235 days apartclk: bcm: dvp: Assign ->num before accessing ->hws
    39Monitor
  • CVE-2021-444035 days apartx86/xen: Drop USERGS_SYSRET64 paravirt call
    35Monitor
  • CVE-2021-473130 days apartcpufreq: CPPC: Fix potential memleak in cppc_cpufreq_cpu_init
    33Monitor
  • CVE-2024-3861629 days apartwifi: carl9170: re-fix fortified-memset warning
    32Monitor
  • CVE-2021-4702383 days apartnet: marvell: prestera: fix port event handling on init
    32Monitor
  • CVE-2024-359481 days apartbcachefs: Check for journal entries overruning end of sb clean section
    31Monitor

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

  • Someone with local access to the system 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
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
High
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

CWE-400 · Uncontrolled Resource Consumption

CVSS vector

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

nvd-secondary

Root cause

Code that parses nested structures sets no depth or size limit. A small input can turn into a disproportionate processing load.

The bug in code

The whole CWE-400 class

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

Vulnerable

ts
function expand(node) {  return node.children.map(expand);}

Fixed

ts
const MAX_DEPTH = 32;function expand(node, depth = 0) {  if (depth > MAX_DEPTH) throw new Error("too deep");  return node.children.map((c) => expand(c, depth + 1));}

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 (7 more)

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

All records