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TI-2020-16178 Aliases CVE-2020-26541GHSA-f823-qm69-5873

The Linux kernel through 5.8.13 does not properly enforce the Secure Boot Forbidden…

Priority LOW 29Published · Updated

Key facts

Attack vector
Local
Privileges required
High
User interaction
Required
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 12 fixed, 1 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.

Summary

The Linux kernel through 5.8.13 does not properly enforce the Secure Boot Forbidden Signature Database (aka dbx) protection mechanism. This affects certs/blacklist.c and certs/system_keyring.c.

Why it matters now

EPSS 0.00528 44th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial Red Hat: 5 advisoriesRed Hat: 12 fixed, 1 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 · 1

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*up to 5.8.13VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions up to 5.8.13 Vulnerable ·Linux

Remediation

Red Hat 5 advisories

  • RHSA-2021:2718 Released 2021-07-20 · Red Hat rating Important
    kernel security and bug fix update
    • Red Hat CodeReady Linux Builder EUS (v. 8.2) kernel-tools-libs-devel-4.18.0-193.60.2.el8_2
    • Red Hat Enterprise Linux BaseOS EUS (v. 8.2) bpftool-4.18.0-193.60.2.el8_2, kernel-4.18.0-193.60.2.el8_2, kernel-abi-whitelists-4.18.0-193.60.2.el8_2 +19
  • RHSA-2021:2719 Released 2021-07-20 · Red Hat rating Important
    kernel-rt security and bug fix update
    • Red Hat Enterprise Linux Real Time EUS (v. 8.2) kernel-rt-4.18.0-193.60.2.rt13.112.el8_2, kernel-rt-core-4.18.0-193.60.2.rt13.112.el8_2, kernel-rt-debug-4.18.0-193.60.2.rt13.112.el8_2 +7
    • Red Hat Enterprise Linux Real Time for NFV EUS (v. 8.2) kernel-rt-4.18.0-193.60.2.rt13.112.el8_2, kernel-rt-core-4.18.0-193.60.2.rt13.112.el8_2, kernel-rt-debug-4.18.0-193.60.2.rt13.112.el8_2 +9
  • RHSA-2021:2666 Released 2021-07-07 · Red Hat rating Important
    kernel security and bug fix update
    • Red Hat CodeReady Linux Builder EUS (v. 8.1) kernel-tools-libs-devel-4.18.0-147.51.1.el8_1
    • Red Hat Enterprise Linux BaseOS EUS (v. 8.1) bpftool-4.18.0-147.51.1.el8_1, kernel-4.18.0-147.51.1.el8_1, kernel-abi-whitelists-4.18.0-147.51.1.el8_1 +19
Show 2 more Red Hat advisories
  • RHSA-2021:2570 Released 2021-06-29 · Red Hat rating Important
    kernel security and bug fix update
    • Red Hat CodeReady Linux Builder (v. 8) kernel-tools-libs-devel-4.18.0-305.7.1.el8_4
    • Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-305.7.1.el8_4, kernel-4.18.0-305.7.1.el8_4, kernel-abi-stablelists-4.18.0-305.7.1.el8_4 +19
  • RHSA-2021:2599 Released 2021-06-29 · Red Hat rating Important
    kernel-rt security and bug fix update
    • Red Hat Enterprise Linux Real Time (v. 8) kernel-rt-4.18.0-305.7.1.rt7.79.el8_4, kernel-rt-core-4.18.0-305.7.1.rt7.79.el8_4, kernel-rt-debug-4.18.0-305.7.1.rt7.79.el8_4 +7
    • Red Hat Enterprise Linux Real Time for NFV (v. 8) kernel-rt-4.18.0-305.7.1.rt7.79.el8_4, kernel-rt-core-4.18.0-305.7.1.rt7.79.el8_4, kernel-rt-debug-4.18.0-305.7.1.rt7.79.el8_4 +9

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 7AffectedNo fix planned: Will not fix
7Server-RHMTC-1.4Fixed—
8Base-RHMTC-1.4Fixed—
Red Hat CodeReady Linux Builder (v. 8)Fixed RHSA-2021:2570
Red Hat CodeReady Linux Builder EUS (v. 8.1)Fixed RHSA-2021:2666
Red Hat CodeReady Linux Builder EUS (v. 8.2)Fixed RHSA-2021:2718
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2021:2570
Red Hat Enterprise Linux BaseOS EUS (v. 8.1)Fixed RHSA-2021:2666
Red Hat Enterprise Linux BaseOS EUS (v. 8.2)Fixed RHSA-2021:2718
Red Hat Enterprise Linux Real Time (v. 8)Fixed RHSA-2021:2599
Red Hat Enterprise Linux Real Time EUS (v. 8.2)Fixed RHSA-2021:2719
Red Hat Enterprise Linux Real Time for NFV (v. 8)Fixed RHSA-2021:2599
Red Hat Enterprise Linux Real Time for NFV EUS (v. 8.2)Fixed RHSA-2021:2719
Not affected: 5 products
  • Red Hat Enterprise Linux 5
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 9
  • Red Hat Enterprise MRG 2

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-26541
  2. 2026-10-03 Alias added: GHSA-f823-qm69-5873

References

Exploit 1

  • 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