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TI-2021-02970 Aliases CVE-2021-4090GHSA-rwxr-f4qj-9x36

Out-of-bounds write in Linux kernel

Priority LOW 31CWE-787Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · None
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-787 and the CVSS impact.

Summary

An out-of-bounds (OOB) memory write flaw was found in the NFSD in the Linux kernel. Missing sanity may lead to a write beyond bmval[bmlen-1] in nfsd4_decode_bitmap4 in fs/nfsd/nfs4xdr.c. In this flaw, a local attacker with user privilege may gain access to out-of-bounds memory, leading to a system integrity and confidentiality threat.

Why it matters now

EPSS 0.00339 27th percentileScored 2026-11-08
Fix Fixed kernel (Linux): 5.15.5

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
Linuxkernel5.11 to before 5.15.55.15.5Patch availableCNA
  • kernel VendorLinux Affected 5.11 to before 5.15.5 Fixed in 5.15.5 Patch available CNA

CPE configurations NVD · 19

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*before 5.16VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.16:-:*:*:*:*:*:*5.16VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.16:rc1:*:*:*:*:*:*5.16 rc1VulnerableLinux
cpe:2.3:o:netapp:h300s_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
cpe:2.3:h:netapp:h300s:-:*:*:*:*:*:*:*not specified by NVDRunning onNetApp
cpe:2.3:o:netapp:h500s_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
cpe:2.3:h:netapp:h500s:-:*:*:*:*:*:*:*not specified by NVDRunning onNetApp
cpe:2.3:o:netapp:h700s_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
cpe:2.3:h:netapp:h700s:-:*:*:*:*:*:*:*not specified by NVDRunning onNetApp
cpe:2.3:o:netapp:h300e_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions before 5.16 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.16:-:*:*:*:*:*:* Versions 5.16 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.16:rc1:*:*:*:*:*:* Versions 5.16 rc1 Vulnerable ·Linux
  • cpe:2.3:o:netapp:h300s_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
  • cpe:2.3:h:netapp:h300s:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
  • cpe:2.3:o:netapp:h500s_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
  • cpe:2.3:h:netapp:h500s:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
  • cpe:2.3:o:netapp:h700s_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
  • cpe:2.3:h:netapp:h700s:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
  • cpe:2.3:o:netapp:h300e_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
Show 9 more CPE
CPEVersionsRoleVendor
cpe:2.3:h:netapp:h300e:-:*:*:*:*:*:*:*not specified by NVDRunning onNetApp
cpe:2.3:o:netapp:h500e_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
cpe:2.3:h:netapp:h500e:-:*:*:*:*:*:*:*not specified by NVDRunning onNetApp
cpe:2.3:o:netapp:h700e_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
cpe:2.3:h:netapp:h700e:-:*:*:*:*:*:*:*not specified by NVDRunning onNetApp
cpe:2.3:o:netapp:h410s_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
cpe:2.3:h:netapp:h410s:-:*:*:*:*:*:*:*not specified by NVDRunning onNetApp
cpe:2.3:o:netapp:h410c_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
cpe:2.3:h:netapp:h410c:-:*:*:*:*:*:*:*not specified by NVDRunning onNetApp
  • cpe:2.3:h:netapp:h300e:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
  • cpe:2.3:o:netapp:h500e_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
  • cpe:2.3:h:netapp:h500e:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
  • cpe:2.3:o:netapp:h700e_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
  • cpe:2.3:h:netapp:h700e:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
  • cpe:2.3:o:netapp:h410s_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
  • cpe:2.3:h:netapp:h410s:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
  • cpe:2.3:o:netapp:h410c_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
  • cpe:2.3:h:netapp:h410c:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp

Remediation

  • Fix · CNA kernel (Linux) Fixed in 5.15.5

Vendor assessments

Red Hat

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

Not affected: 4 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-4090
  2. 2026-10-03 Alias added: GHSA-rwxr-f4qj-9x36

References

Patch 1

Advisory 1

Other 2

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources

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