Skip to content
Noroxi
NVD / CVE Program· CNA Google

CVE-2021-22600: Double Free in net/packet/af_packet.c leading to priviledge escalation

Noroxi assessment

Priority: This week (action score 60/100)

  • CISA has confirmed exploitation in the wild (Apr 11, 2022). Remediation deadline for US federal agencies: May 2, 2022.
  • Probability of exploitation in the next 30 days: 6.5% (FIRST EPSS); higher than 93.8% of all records.
  • 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 (Debian:10) 4.19.232-1; linux (Debian:12) 5.15.15-1; linux-4.19 (Debian:9) 4.19.232-1~deb9u1.

Don’t wait for the next maintenance window. Upgrade to linux (Debian:10) 4.19.232-1; linux (Debian:12) 5.15.15-1; linux-4.19 (Debian:9) 4.19.232-1~deb9u1 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 · CISA KEV · FIRST EPSS

A double free bug in packet_set_ring() in net/packet/af_packet.c can be exploited by a local user through crafted syscalls to escalate privileges or deny service. We recommend upgrading kernel past the effected versions or rebuilding past ec6af094ea28f0f2dda1a6a33b14cd57e36a9755

HighCVSS 7.0 · v3.1KEVWeaponized Fix available
Published
Jan 26, 2022
Updated
Jun 16, 2026
EPSS
6.5% · 93th percentile

Report tools

JSON

Action score

60

This week

Don’t wait for the next maintenance window.

CVSS
28 / 40 · 7.0 / 10
CISA KEV
30 / 30 · Listed
EPSS
2 / 30 · 6.5%

CISA SSVC decision

Exploitation
active
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
7.0
CNA · Google
6.6
0.4 point gap

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

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

Actively exploited in the wild

CISA added this to its Known Exploited Vulnerabilities catalog on Apr 11, 2022. That signals real attacks, not theory.

Remediation deadline for US federal agencies: May 2, 2022.

Get told when this record changes

  • In CISA KEV: exploitation in the wild confirmed
  • Weaponized exploit exists
  • A fix has been released

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

Follow CVE-2021-22600

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 instantly.

Your free account also gets you

Running WordPress? Scan your site free with WP Lens

  • Stack 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 (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 netapp records

Running WordPress? Scan your site free with WP Lens

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
netapp8300 firmware
netapp8300
netapp8700 firmware
netapp8700
netappa400 firmware
netappa400
netappc400 firmware
netappc400
netapph410c firmware
netapph410c
netapph300s firmware
netapph300s

and 8 more

Affected versions

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

  • debian debian linux10.0
  • debian debian linux9.0
  • linux linux kernel4.14.175 and later · before 4.14.259
  • linux linux kernel4.19.114 and later · before 4.19.222
  • linux linux kernel5.4.29 and later · before 5.4.168
  • linux linux kernel5.11 and later · before 5.15.11
  • linux linux kernel5.5.14 and later · before 5.10.88
  • netapp 8300 firmwareall versions
  • netapp 8700 firmwareall versions
  • netapp a400 firmwareall versions
  • netapp c400 firmwareall versions
  • netapp h300s firmwareall versions
  • netapp h410c firmwareall versions
  • netapp h410s firmwareall versions
  • netapp h500s firmwareall versions
  • netapp h700s firmwareall versions

Versions reported by the vendor

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

  • Linux Kernel Kernel

    • unspecified and later · before 5.4.168affected
    • unspecified and later · before 5.10.88affected
    • unspecified and later · before 5.15.11affected
    • unspecified and later · before 5.16-rc6affected

Package-level exposure

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

EcosystemPackageAffected rangeFix
Debian:10linuxbefore 4.19.232-14.19.232-1
Debian:12linuxbefore 5.15.15-15.15.15-1
Debian:9linux-4.19before 4.19.232-1~deb9u14.19.232-1~deb9u1
openSUSE:Leap 15.3dtb-aarch64before 5.3.18-150300.59.49.15.3.18-150300.59.49.1
openSUSE:Leap 15.3kernel-64kbbefore 5.3.18-150300.59.49.15.3.18-150300.59.49.1
openSUSE:Leap 15.3kernel-azurebefore 5.3.18-150300.38.40.45.3.18-150300.38.40.4
openSUSE:Leap 15.3kernel-debugbefore 5.3.18-150300.59.49.15.3.18-150300.59.49.1
openSUSE:Leap 15.3kernel-defaultbefore 5.3.18-150300.59.49.15.3.18-150300.59.49.1
openSUSE:Leap 15.3kernel-default-basebefore 5.3.18-150300.59.49.1.150300.18.31.15.3.18-150300.59.49.1.150300.18.31.1
openSUSE:Leap 15.3kernel-docsbefore 5.3.18-150300.59.49.15.3.18-150300.59.49.1
openSUSE:Leap 15.3kernel-kvmsmallbefore 5.3.18-150300.59.49.15.3.18-150300.59.49.1
openSUSE:Leap 15.3kernel-obs-buildbefore 5.3.18-150300.59.49.15.3.18-150300.59.49.1
openSUSE:Leap 15.3kernel-obs-qabefore 5.3.18-150300.59.49.15.3.18-150300.59.49.1
openSUSE:Leap 15.3kernel-preemptbefore 5.3.18-150300.59.49.15.3.18-150300.59.49.1
openSUSE:Leap 15.3kernel-sourcebefore 5.3.18-150300.59.49.15.3.18-150300.59.49.1
openSUSE:Leap 15.3kernel-source-azurebefore 5.3.18-150300.38.40.45.3.18-150300.38.40.4
openSUSE:Leap 15.3kernel-symsbefore 5.3.18-150300.59.49.15.3.18-150300.59.49.1
openSUSE:Leap 15.3kernel-syms-azurebefore 5.3.18-150300.38.40.15.3.18-150300.38.40.1
openSUSE:Leap 15.3kernel-zfcpdumpbefore 5.3.18-150300.59.49.15.3.18-150300.59.49.1
SUSE:Linux Enterprise High Performance Computing 15 SP2-ESPOSkernel-default-basebefore 5.3.18-24.102.1.9.48.15.3.18-24.102.1.9.48.1
SUSE:Linux Enterprise High Performance Computing 15 SP2-ESPOSkernel-docsbefore 5.3.18-24.102.15.3.18-24.102.1
SUSE:Linux Enterprise High Performance Computing 15 SP2-ESPOSkernel-obs-buildbefore 5.3.18-24.102.15.3.18-24.102.1
SUSE:Linux Enterprise High Performance Computing 15 SP2-ESPOSkernel-preemptbefore 5.3.18-24.102.15.3.18-24.102.1
SUSE:Linux Enterprise High Performance Computing 15 SP2-ESPOSkernel-sourcebefore 5.3.18-24.102.15.3.18-24.102.1

+50

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:linux5.15.15-1 · Debian:12Package registry (OSV)
debian:linux-4.194.19.232-1~deb9u1 · Debian:9Package registry (OSV)
opensuse:dtb-aarch645.3.18-150300.59.49.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-64kb5.3.18-150300.59.49.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-azure5.3.18-150300.38.40.4 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-debug5.3.18-150300.59.49.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-default5.3.18-150300.59.49.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-default-base5.3.18-150300.59.49.1.150300.18.31.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-docs5.3.18-150300.59.49.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-kvmsmall5.3.18-150300.59.49.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-obs-build5.3.18-150300.59.49.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-obs-qa5.3.18-150300.59.49.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-source-azure5.3.18-150300.38.40.4 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-syms-azure5.3.18-150300.38.40.1 · openSUSE:Leap 15.3Package registry (OSV)
suse:kernel-64kb5.3.18-150300.59.49.1 · SUSE:Linux Enterprise Module for Basesystem 15 SP3Package registry (OSV)
suse:kernel-azure5.3.18-150300.38.40.4 · SUSE:Linux Enterprise Module for Public Cloud 15 SP3Package registry (OSV)
suse:kernel-default5.3.18-24.102.1 · SUSE:Linux Enterprise Live Patching 15 SP2Package registry (OSV)
suse:kernel-default-base5.3.18-24.102.1.9.48.1 · SUSE:Linux Enterprise High Performance Computing 15 SP2-ESPOSPackage registry (OSV)
suse:kernel-docs5.3.18-24.102.1 · SUSE:Linux Enterprise High Performance Computing 15 SP2-ESPOSPackage registry (OSV)
suse:kernel-livepatch-SLE15-SP2_Update_241-5.3.1 · SUSE:Linux Enterprise Live Patching 15 SP2Package registry (OSV)
suse:kernel-obs-build5.3.18-24.102.1 · SUSE:Linux Enterprise High Performance Computing 15 SP2-ESPOSPackage registry (OSV)
suse:kernel-preempt5.3.18-24.102.1 · SUSE:Linux Enterprise High Performance Computing 15 SP2-ESPOSPackage registry (OSV)
suse:kernel-source5.3.18-24.102.1 · SUSE:Linux Enterprise High Performance Computing 15 SP2-ESPOSPackage registry (OSV)
suse:kernel-source-azure5.3.18-150300.38.40.4 · SUSE:Linux Enterprise Module for Public Cloud 15 SP3Package registry (OSV)
suse:kernel-syms5.3.18-24.102.1 · SUSE:Linux Enterprise High Performance Computing 15 SP2-ESPOSPackage registry (OSV)
suse:kernel-syms-azure5.3.18-150300.38.40.1 · SUSE:Linux Enterprise Module for Public Cloud 15 SP3Package registry (OSV)

Exploit status

Weaponized

A ready exploit tool or active in-the-wild use is known for this vulnerability. This should be your top priority.

Evidence

  • Proof-of-concept repository on GitHub ×2

Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.

Public exploit evidence
SourceKindDate
Proof-of-concept repository on GitHubstars:12025-06-22
Proof-of-concept repository on GitHubstars:12025-09-17

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.

  1. Published
  2. CISA KEV+75 d
  3. First PoC+1243 d
  4. TodayOct 31, 2026+1739 d

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.
  • 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
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
High
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-415 · Double Free

CVSS vector

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

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