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TI-2020-15453 Aliases CVE-2020-25212GHSA-w56x-hj26-mq65

A TOCTOU mismatch in the NFS client code in the Linux kernel before 5.8.3 could be used…

Priority LOW 31CWE-367Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
High
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 30 fixed, 3 without a fix

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

Summary

A TOCTOU mismatch in the NFS client code in the Linux kernel before 5.8.3 could be used by local attackers to corrupt memory or possibly have unspecified other impact because a size check is in fs/nfs/nfs4proc.c instead of fs/nfs/nfs4xdr.c, aka CID-b4487b935452.

Why it matters now

EPSS 0.00277 20th percentileScored 2026-11-07
Fix Partial Red Hat: 8 advisoriesRed Hat: 30 fixed, 3 without a fix

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 8

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*before 5.8.3VulnerableLinux
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*9.0VulnerableDebian
cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*15.1VulnerableopenSUSE
cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:*15.2VulnerableopenSUSE
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:esm:*:*:*14.04VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:*16.04VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*18.04VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:*20.04VulnerableCanonical
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions before 5.8.3 Vulnerable ·Linux
  • cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Debian
  • cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:* Versions 15.1 Vulnerable ·openSUSE
  • cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:* Versions 15.2 Vulnerable ·openSUSE
  • cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:esm:*:*:* Versions 14.04 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:* Versions 16.04 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:* Versions 18.04 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:* Versions 20.04 Vulnerable ·Canonical

Remediation

Red Hat 8 advisories

  • RHSA-2021:1739 Released 2021-05-18 · Red Hat rating Important
    kernel-rt security and bug fix update
    • Red Hat Enterprise Linux Real Time (v. 8) kernel-rt-4.18.0-305.rt7.72.el8, kernel-rt-core-4.18.0-305.rt7.72.el8, kernel-rt-debug-4.18.0-305.rt7.72.el8 +7
    • Red Hat Enterprise Linux Real Time for NFV (v. 8) kernel-rt-4.18.0-305.rt7.72.el8, kernel-rt-core-4.18.0-305.rt7.72.el8, kernel-rt-debug-4.18.0-305.rt7.72.el8 +9
  • RHSA-2021:1578 Released 2021-05-18 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat CodeReady Linux Builder (v. 8) kernel-tools-libs-devel-4.18.0-305.el8
    • Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-305.el8, kernel-4.18.0-305.el8, kernel-abi-stablelists-4.18.0-305.el8 +19
  • RHSA-2021:0878 Released 2021-03-16 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux ComputeNode EUS (v. 7.6) bpftool-3.10.0-957.70.1.el7, kernel-3.10.0-957.70.1.el7, kernel-abi-whitelists-3.10.0-957.70.1.el7 +8
    • Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.6) kernel-tools-libs-devel-3.10.0-957.70.1.el7
    • Red Hat Enterprise Linux Server EUS (v. 7.6) bpftool-3.10.0-957.70.1.el7, kernel-3.10.0-957.70.1.el7, kernel-abi-whitelists-3.10.0-957.70.1.el7 +11
    • Red Hat Enterprise Linux Server Optional EUS (v. 7.6) kernel-debug-devel-3.10.0-957.70.1.el7, kernel-tools-libs-devel-3.10.0-957.70.1.el7
    • Red Hat Virtualization 4.2 Hypervisor for RHEL 7.6 EUS kernel-devel-3.10.0-957.70.1.el7, perf-3.10.0-957.70.1.el7, python-perf-3.10.0-957.70.1.el7
Show 5 more Red Hat advisories
  • RHSA-2021:0760 Released 2021-03-09 · Red Hat rating Moderate
    kernel security and bug fix update
    • Red Hat Enterprise Linux Server AUS (v. 7.4) kernel-3.10.0-693.82.1.el7, kernel-abi-whitelists-3.10.0-693.82.1.el7, kernel-debug-3.10.0-693.82.1.el7 +7
    • Red Hat Enterprise Linux Server E4S (v. 7.4) kernel-3.10.0-693.82.1.el7, kernel-abi-whitelists-3.10.0-693.82.1.el7, kernel-bootwrapper-3.10.0-693.82.1.el7 +8
    • Red Hat Enterprise Linux Server Optional AUS (v. 7.4) kernel-tools-libs-devel-3.10.0-693.82.1.el7
    • Red Hat Enterprise Linux Server Optional E4S (v. 7.4) kernel-debug-devel-3.10.0-693.82.1.el7, kernel-tools-libs-devel-3.10.0-693.82.1.el7
    • Red Hat Enterprise Linux Server Optional TUS (v. 7.4) kernel-tools-libs-devel-3.10.0-693.82.1.el7
    • Red Hat Enterprise Linux Server TUS (v. 7.4) kernel-3.10.0-693.82.1.el7, kernel-abi-whitelists-3.10.0-693.82.1.el7, kernel-debug-3.10.0-693.82.1.el7 +7
  • RHSA-2021:0526 Released 2021-02-16 · Red Hat rating Moderate
    kernel security and bug fix update
    • Red Hat Enterprise Linux ComputeNode EUS (v. 7.7) bpftool-3.10.0-1062.45.1.el7, kernel-3.10.0-1062.45.1.el7, kernel-abi-whitelists-3.10.0-1062.45.1.el7 +8
    • Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.7) kernel-tools-libs-devel-3.10.0-1062.45.1.el7
    • Red Hat Enterprise Linux Server EUS (v. 7.7) bpftool-3.10.0-1062.45.1.el7, kernel-3.10.0-1062.45.1.el7, kernel-abi-whitelists-3.10.0-1062.45.1.el7 +11
    • Red Hat Enterprise Linux Server Optional EUS (v. 7.7) kernel-debug-devel-3.10.0-1062.45.1.el7, kernel-tools-libs-devel-3.10.0-1062.45.1.el7
  • RHSA-2020:5437 Released 2020-12-15 · Red Hat rating Important
    kernel security and bug fix update
    • Red Hat Enterprise Linux Client (v. 7) bpftool-3.10.0-1160.11.1.el7, kernel-3.10.0-1160.11.1.el7, kernel-abi-whitelists-3.10.0-1160.11.1.el7 +8
    • Red Hat Enterprise Linux Client Optional (v. 7) kernel-tools-libs-devel-3.10.0-1160.11.1.el7
    • Red Hat Enterprise Linux ComputeNode Optional (v. 7) kernel-tools-libs-devel-3.10.0-1160.11.1.el7
    • Red Hat Enterprise Linux Server (v. 7) bpftool-3.10.0-1160.11.1.el7, kernel-3.10.0-1160.11.1.el7, kernel-abi-whitelists-3.10.0-1160.11.1.el7 +11
    • Red Hat Enterprise Linux Server Optional (v. 7) kernel-debug-devel-3.10.0-1160.11.1.el7, kernel-tools-libs-devel-3.10.0-1160.11.1.el7
    • Red Hat Enterprise Linux Workstation (v. 7) bpftool-3.10.0-1160.11.1.el7, kernel-3.10.0-1160.11.1.el7, kernel-abi-whitelists-3.10.0-1160.11.1.el7 +8
    • Red Hat Enterprise Linux Workstation Optional (v. 7) kernel-tools-libs-devel-3.10.0-1160.11.1.el7
  • RHSA-2020:5441 Released 2020-12-15 · Red Hat rating Important
    kernel-rt security and bug fix update
    • Red Hat Enterprise Linux for Real Time (v. 7) kernel-rt-3.10.0-1160.11.1.rt56.1145.el7, kernel-rt-debug-3.10.0-1160.11.1.rt56.1145.el7, kernel-rt-debug-devel-3.10.0-1160.11.1.rt56.1145.el7 +4
    • Red Hat Enterprise Linux for Real Time for NFV (v. 7) kernel-rt-3.10.0-1160.11.1.rt56.1145.el7, kernel-rt-debug-3.10.0-1160.11.1.rt56.1145.el7, kernel-rt-debug-devel-3.10.0-1160.11.1.rt56.1145.el7 +7
  • RHSA-2020:4279 Released 2020-10-19 · Red Hat rating Important
    kernel-alt security update
    • Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server (v. 7) kernel-4.14.0-115.32.1.el7a, kernel-abi-whitelists-4.14.0-115.32.1.el7a, kernel-alt-4.14.0-115.32.1.el7a +8
    • Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server Optional (v. 7) kernel-debug-devel-4.14.0-115.32.1.el7a, kernel-tools-libs-devel-4.14.0-115.32.1.el7a

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 5AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise MRG 2AffectedNo fix planned: Out of support scope
Red Hat CodeReady Linux Builder (v. 8)Fixed RHSA-2021:1578
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2021:1578
Red Hat Enterprise Linux Client (v. 7)Fixed RHSA-2020:5437
Red Hat Enterprise Linux Client Optional (v. 7)Fixed RHSA-2020:5437
Red Hat Enterprise Linux ComputeNode EUS (v. 7.6)Fixed RHSA-2021:0878
Red Hat Enterprise Linux ComputeNode EUS (v. 7.7)Fixed RHSA-2021:0526
Red Hat Enterprise Linux ComputeNode Optional (v. 7)Fixed RHSA-2020:5437
Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.6)Fixed RHSA-2021:0878
Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.7)Fixed RHSA-2021:0526
Red Hat Enterprise Linux Real Time (v. 8)Fixed RHSA-2021:1739
Red Hat Enterprise Linux Real Time for NFV (v. 8)Fixed RHSA-2021:1739
Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2020:5437
Red Hat Enterprise Linux Server AUS (v. 7.4)Fixed RHSA-2021:0760
Red Hat Enterprise Linux Server E4S (v. 7.4)Fixed RHSA-2021:0760
Red Hat Enterprise Linux Server EUS (v. 7.6)Fixed RHSA-2021:0878
Red Hat Enterprise Linux Server EUS (v. 7.7)Fixed RHSA-2021:0526
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2020:5437
Red Hat Enterprise Linux Server Optional AUS (v. 7.4)Fixed RHSA-2021:0760
Red Hat Enterprise Linux Server Optional E4S (v. 7.4)Fixed RHSA-2021:0760
Red Hat Enterprise Linux Server Optional EUS (v. 7.6)Fixed RHSA-2021:0878
Red Hat Enterprise Linux Server Optional EUS (v. 7.7)Fixed RHSA-2021:0526
Red Hat Enterprise Linux Server Optional TUS (v. 7.4)Fixed RHSA-2021:0760
Red Hat Enterprise Linux Server TUS (v. 7.4)Fixed RHSA-2021:0760
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2020:5437
Red Hat Enterprise Linux Workstation Optional (v. 7)Fixed RHSA-2020:5437
Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server (v. 7)Fixed RHSA-2020:4279
Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server Optional (v. 7)Fixed RHSA-2020:4279
Red Hat Enterprise Linux for Real Time (v. 7)Fixed RHSA-2020:5441
Red Hat Enterprise Linux for Real Time for NFV (v. 7)Fixed RHSA-2020:5441
Red Hat Virtualization 4.2 Hypervisor for RHEL 7.6 EUSFixed RHSA-2021:0878
Not affected: 5 products
  • Red Hat Enterprise Linux ComputeNode EUS (v. 7.7)
  • Red Hat Enterprise Linux Server AUS (v. 7.4)
  • Red Hat Enterprise Linux Server E4S (v. 7.4)
  • Red Hat Enterprise Linux Server EUS (v. 7.7)
  • Red Hat Enterprise Linux Server TUS (v. 7.4)

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-25212
  2. 2026-10-03 Alias added: GHSA-w56x-hj26-mq65

References

Patch 1

Advisory 11

Sources

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