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TI-2021-02580 Aliases CVE-2021-3635GHSA-3rcv-mwcm-8g8f

Memory corruption in kernel

Priority LOW 20CWE-119Published · Updated

Key facts

Attack vector
Local
Privileges required
High
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 4 fixed, 2 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-119 and the CVSS impact.

Summary

A flaw was found in the Linux kernel netfilter implementation in versions prior to 5.5-rc7. A user with root (CAP_SYS_ADMIN) access is able to panic the system when issuing netfilter netflow commands.

Why it matters now

EPSS 0.00248 16th percentileScored 2026-11-07
Fix Partial Red Hat: 2 advisoriesRed Hat: 4 fixed, 2 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
—kernelkernel 5.5-rc7—No fix listedCNA
  • kernel Vendor— Affected kernel 5.5-rc7 Fixed in — No fix listed CNA

CPE configurations NVD · 11

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*before 5.5VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.5:rc1:*:*:*:*:*:*5.5 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.5:rc2:*:*:*:*:*:*5.5 rc2VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.5:rc3:*:*:*:*:*:*5.5 rc3VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.5:rc4:*:*:*:*:*:*5.5 rc4VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.5:rc5:*:*:*:*:*:*5.5 rc5VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.5:rc6:*:*:*:*:*:*5.5 rc6VulnerableLinux
cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*6.0VulnerableRed Hat
cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*7.0VulnerableRed Hat
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*8.0VulnerableRed Hat
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions before 5.5 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.5:rc1:*:*:*:*:*:* Versions 5.5 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.5:rc2:*:*:*:*:*:* Versions 5.5 rc2 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.5:rc3:*:*:*:*:*:* Versions 5.5 rc3 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.5:rc4:*:*:*:*:*:* Versions 5.5 rc4 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.5:rc5:*:*:*:*:*:* Versions 5.5 rc5 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.5:rc6:*:*:*:*:*:* Versions 5.5 rc6 Vulnerable ·Linux
  • cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:* Versions 6.0 Vulnerable ·Red Hat
  • cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:* Versions 7.0 Vulnerable ·Red Hat
  • cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:* Versions 8.0 Vulnerable ·Red Hat
Show 1 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*34VulnerableFedoraproject
  • cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* Versions 34 Vulnerable ·Fedoraproject

Remediation

Red Hat 2 advisories

  • RHSA-2021:4356 Released 2021-11-09 · Red Hat rating Moderate
    kernel security, bug fix, and enhancement update
    • Red Hat CodeReady Linux Builder (v. 8) kernel-tools-libs-devel-4.18.0-348.el8
    • Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-348.el8, kernel-4.18.0-348.el8, kernel-abi-stablelists-4.18.0-348.el8 +19
  • RHSA-2021:4140 Released 2021-11-09 · Red Hat rating Moderate
    kernel-rt security and bug fix update
    • Red Hat Enterprise Linux Real Time (v. 8) kernel-rt-4.18.0-348.rt7.130.el8, kernel-rt-core-4.18.0-348.rt7.130.el8, kernel-rt-debug-4.18.0-348.rt7.130.el8 +7
    • Red Hat Enterprise Linux Real Time for NFV (v. 8) kernel-rt-4.18.0-348.rt7.130.el8, kernel-rt-core-4.18.0-348.rt7.130.el8, kernel-rt-debug-4.18.0-348.rt7.130.el8 +9

Vendor assessments

Red Hat

Red Hat rating: Low. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix planned: Will not fix
Red Hat CodeReady Linux Builder (v. 8)Fixed RHSA-2021:4356
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2021:4356
Red Hat Enterprise Linux Real Time (v. 8)Fixed RHSA-2021:4140
Red Hat Enterprise Linux Real Time for NFV (v. 8)Fixed RHSA-2021:4140
Not affected: 1 product
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-3635
  2. 2026-10-03 Alias added: GHSA-3rcv-mwcm-8g8f

References

Advisory 1

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences