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NVD / CVE Program· CNA redhat

CVE-2021-3772: A flaw was found in the Linux SCTP stack.

Noroxi assessment

Priority: Monitor (action score 26/100)

  • 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: 1.2% (FIRST EPSS); higher than 68.9% of all records.
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. Special conditions such as timing or configuration are required.
  • Fixed version: bpftool (AlmaLinux:8) 4.18.0-372.9.1.el8; kernel (AlmaLinux:8) 4.18.0-372.9.1.el8; kernel-abi-stablelists (AlmaLinux:8) 4.18.0-372.9.1.el8.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to bpftool (AlmaLinux:8) 4.18.0-372.9.1.el8; kernel (AlmaLinux:8) 4.18.0-372.9.1.el8; kernel-abi-stablelists (AlmaLinux:8) 4.18.0-372.9.1.el8 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 SCTP stack. A blind attacker may be able to kill an existing SCTP association through invalid chunks if the attacker knows the IP-addresses and port numbers being used and the attacker can send packets with spoofed IP addresses.

MediumCVSS 6.5 · v3.1—No exploit Fix available
Published
Mar 2, 2022
Updated
Jun 17, 2026
EPSS
1.2% · 68th percentile

Report tools

JSON

Action score

26

Monitor

Low priority for now.

CVSS
26 / 40 · 6.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 1.2%

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  • 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
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  • 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
debiandebian linux
oraclecommunications cloud native core binding support function
oraclecommunications cloud native core network exposure function
oraclecommunications cloud native core policy
netappe-series santricity os controller
netappsolidfire \& hci management node
netappsolidfire \& hci storage node
netapphci compute node
netapph300s firmware
netapph300s

and 14 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 kernelbefore 5.15.0
  • netapp e-series santricity os controller11.0
  • netapp e-series santricity os controller11.0.0
  • netapp e-series santricity os controller11.20
  • netapp e-series santricity os controller11.25
  • netapp e-series santricity os controller11.30
  • netapp e-series santricity os controller11.30.5r3
  • netapp e-series santricity os controller11.40
  • netapp e-series santricity os controller11.40.3r2
  • netapp e-series santricity os controller11.40.5
  • netapp e-series santricity os controller11.50.1
  • netapp e-series santricity os controller11.50.2
  • netapp e-series santricity os controller11.60
  • netapp e-series santricity os controller11.60.0
  • netapp e-series santricity os controller11.60.1
  • netapp e-series santricity os controller11.60.3
  • netapp e-series santricity os controller11.70.1
  • netapp e-series santricity os controller11.70.2

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

    • Fixed in linux kernel v5.15 and aboveaffected

Package-level exposure

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

EcosystemPackageAffected rangeFix
AlmaLinux:8bpftoolbefore 4.18.0-372.9.1.el84.18.0-372.9.1.el8
AlmaLinux:8kernelbefore 4.18.0-372.9.1.el84.18.0-372.9.1.el8
AlmaLinux:8kernel-abi-stablelistsbefore 4.18.0-372.9.1.el84.18.0-372.9.1.el8
AlmaLinux:8kernel-corebefore 4.18.0-372.9.1.el84.18.0-372.9.1.el8
AlmaLinux:8kernel-cross-headersbefore 4.18.0-372.9.1.el84.18.0-372.9.1.el8
AlmaLinux:8kernel-debugbefore 4.18.0-372.9.1.el84.18.0-372.9.1.el8
AlmaLinux:8kernel-debug-corebefore 4.18.0-372.9.1.el84.18.0-372.9.1.el8
AlmaLinux:8kernel-debug-develbefore 4.18.0-372.9.1.el84.18.0-372.9.1.el8
AlmaLinux:8kernel-debug-modulesbefore 4.18.0-372.9.1.el84.18.0-372.9.1.el8
AlmaLinux:8kernel-debug-modules-extrabefore 4.18.0-372.9.1.el84.18.0-372.9.1.el8
AlmaLinux:8kernel-develbefore 4.18.0-372.9.1.el84.18.0-372.9.1.el8
AlmaLinux:8kernel-docbefore 4.18.0-372.9.1.el84.18.0-372.9.1.el8
AlmaLinux:8kernel-headersbefore 4.18.0-372.9.1.el84.18.0-372.9.1.el8
AlmaLinux:8kernel-modulesbefore 4.18.0-372.9.1.el84.18.0-372.9.1.el8
AlmaLinux:8kernel-modules-extrabefore 4.18.0-372.9.1.el84.18.0-372.9.1.el8
AlmaLinux:8kernel-toolsbefore 4.18.0-372.9.1.el84.18.0-372.9.1.el8
AlmaLinux:8kernel-tools-libsbefore 4.18.0-372.9.1.el84.18.0-372.9.1.el8
AlmaLinux:8kernel-tools-libs-develbefore 4.18.0-372.9.1.el84.18.0-372.9.1.el8
AlmaLinux:8perfbefore 4.18.0-372.9.1.el84.18.0-372.9.1.el8
AlmaLinux:8python3-perfbefore 4.18.0-372.9.1.el84.18.0-372.9.1.el8
Debian:10linuxbefore 4.19.232-14.19.232-1
Debian:12linuxbefore 5.14.16-15.14.16-1
Debian:9linux-4.19before 4.19.232-1~deb9u14.19.232-1~deb9u1
openSUSE:Leap 15.2kernel-debugbefore 5.3.18-lp152.102.15.3.18-lp152.102.1

+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-2020-36516Feb 26, 2022 · An issue was discovered in the Linux kernel through 5.16.11.
    23Monitor
  • ← EarlierCVE-2021-3715Mar 2, 2022 · A flaw was found in the "Routing decision" classifier in the Linux kernel's Traffic Control networking subsystem in the way it handled chang
    31Monitor
  • Later →CVE-2021-3609Mar 3, 2022 · .A flaw was found in the CAN BCM networking protocol in the Linux kernel, where a local attacker can abuse a flaw in the CAN subsystem to co
    28Monitor

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
almalinux:bpftool4.18.0-372.9.1.el8 · AlmaLinux:8Package registry (OSV)
almalinux:kernel4.18.0-372.9.1.el8 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-abi-stablelists4.18.0-372.9.1.el8 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-core4.18.0-372.9.1.el8 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-cross-headers4.18.0-372.9.1.el8 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-debug4.18.0-372.9.1.el8 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-debug-core4.18.0-372.9.1.el8 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-debug-devel4.18.0-372.9.1.el8 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-debug-modules4.18.0-372.9.1.el8 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-debug-modules-extra4.18.0-372.9.1.el8 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-devel4.18.0-372.9.1.el8 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-doc4.18.0-372.9.1.el8 · AlmaLinux:8Package registry (OSV)
debian:linux5.14.16-1 · Debian:12Package registry (OSV)
debian:linux-4.194.19.232-1~deb9u1 · Debian:9Package registry (OSV)
opensuse:kernel-azure5.3.18-38.28.2 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-debug5.3.18-lp152.102.1 · openSUSE:Leap 15.2Package registry (OSV)
opensuse:kernel-default5.3.18-lp152.102.1 · openSUSE:Leap 15.2Package registry (OSV)
opensuse:kernel-default-base5.3.18-lp152.102.1.lp152.8.49.1 · openSUSE:Leap 15.2Package registry (OSV)
opensuse:kernel-docs5.3.18-lp152.102.1 · openSUSE:Leap 15.2Package registry (OSV)
opensuse:kernel-kvmsmall5.3.18-lp152.102.1 · openSUSE:Leap 15.2Package registry (OSV)
opensuse:kernel-obs-build5.3.18-lp152.102.1 · openSUSE:Leap 15.2Package registry (OSV)
opensuse:kernel-obs-qa5.3.18-lp152.102.1 · openSUSE:Leap 15.2Package registry (OSV)
opensuse:kernel-preempt5.3.18-lp152.102.1 · openSUSE:Leap 15.2Package registry (OSV)
opensuse:kernel-source5.3.18-lp152.102.1 · openSUSE:Leap 15.2Package registry (OSV)
opensuse:kernel-source-azure5.3.18-38.28.2 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:kernel-syms5.3.18-lp152.102.1 · openSUSE:Leap 15.2Package 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)

+22

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.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

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.
  • No account or password is required.
  • No user action is required.
  • Special conditions such as timing or configuration are required.

If successful

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

Weakness class (CWE)

CWE-354 · Improper Validation of Integrity Check Value

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/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 (7 more)

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

All records