Is CVE-2025-21998 in the CISA KEV catalog?

No. CVE-2025-21998 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2025-21998?

CVE-2025-21998 has a CVSS v3 base score of 4.7 (MEDIUM).

What is the EPSS score for CVE-2025-21998?

CVE-2025-21998 has an EPSS score of 0.13% (3th percentile), estimating the probability of exploitation in the next 30 days.

How do I fix CVE-2025-21998?

Upgrade linux on debian 13 to 6.12.21-1 or later. Fixes are available for 30 affected products.

CVE & CISA-KEV Catalog

CVE-2025-21998

MEDIUM

4.7

CVSS v3

NVD

Description

In the Linux kernel, the following vulnerability has been resolved: firmware: qcom: uefisecapp: fix efivars registration race Since the conversion to using the TZ allocator, the efivars service is registered before the memory pool has been allocated, something which can lead to a NULL-pointer dereference in case of a racing EFI variable access. Make sure that all resources have been set up before registering the efivars.

CWE-367TOCTOU Race Condition CWE-476NULL Pointer Dereference

How to fix

Remediation Available

linuxDebian

Fixed in:6.12.21-1CVE-2025-21998

linux-azure-6.11Ubuntu

Fixed in:6.11.0-1018.18~24.04.1USN-7628-1

linux-gcp-6.11Ubuntu

Fixed in:6.11.0-1016.16~24.04.1USN-7605-1

linux-hwe-6.11Ubuntu

Fixed in:6.11.0-28.28~24.04.1USN-7605-1

linux-image-6.11.0-1015-lowlatencyUbuntu

Fixed in:6.11.0-1015.16~24.04.2USN-7605-2

linux-image-6.11.0-1015-lowlatency-64kUbuntu

Fixed in:6.11.0-1015.16~24.04.2USN-7605-2

linux-image-6.11.0-1016-gcpUbuntu

Fixed in:6.11.0-1016.16~24.04.1USN-7605-1

linux-image-6.11.0-1016-gcp-64kUbuntu

Fixed in:6.11.0-1016.16~24.04.1USN-7605-1

linux-image-6.11.0-1018-azureUbuntu

Fixed in:6.11.0-1018.18~24.04.1USN-7628-1

linux-image-6.11.0-1018-azure-fdeUbuntu

Fixed in:6.11.0-1018.18~24.04.1USN-7628-1

linux-image-6.11.0-1024-oemUbuntu

Fixed in:6.11.0-1024.24USN-7606-1

linux-image-6.11.0-28-genericUbuntu

Fixed in:6.11.0-28.28~24.04.1USN-7605-1

linux-image-6.11.0-28-generic-64kUbuntu

Fixed in:6.11.0-28.28~24.04.1USN-7605-1

linux-image-azureUbuntu

Fixed in:6.11.0-1018.18~24.04.1USN-7628-1

linux-image-azure-6.11Ubuntu

Fixed in:6.11.0-1018.18~24.04.1USN-7628-1

linux-image-azure-fdeUbuntu

Fixed in:6.11.0-1018.18~24.04.1USN-7628-1

linux-image-azure-fde-6.11Ubuntu

Fixed in:6.11.0-1018.18~24.04.1USN-7628-1

linux-image-azure-fde-edgeUbuntu

Fixed in:6.11.0-1018.18~24.04.1USN-7628-1

linux-image-gcpUbuntu

Fixed in:6.11.0-1016.16~24.04.1USN-7605-1

linux-image-gcp-64kUbuntu

Fixed in:6.11.0-1016.16~24.04.1USN-7605-1

linux-image-generic-64k-hwe-24.04Ubuntu

Fixed in:6.11.0-28.28~24.04.1USN-7605-1

linux-image-generic-hwe-24.04Ubuntu

Fixed in:6.11.0-28.28~24.04.1USN-7605-1

linux-image-lowlatency-6.11Ubuntu

Fixed in:6.11.0-1015.16~24.04.2USN-7605-2

linux-image-lowlatency-64k-6.11Ubuntu

Fixed in:6.11.0-1015.16~24.04.2USN-7605-2

linux-image-lowlatency-64k-hwe-24.04Ubuntu

Fixed in:6.11.0-1015.16~24.04.2USN-7605-2

linux-image-lowlatency-hwe-24.04Ubuntu

Fixed in:6.11.0-1015.16~24.04.2USN-7605-2

linux-image-oem-24.04bUbuntu

Fixed in:6.11.0-1024.24USN-7606-1

linux-image-virtual-hwe-24.04Ubuntu

Fixed in:6.11.0-28.28~24.04.1USN-7605-1

linux-lowlatency-hwe-6.11Ubuntu

Fixed in:6.11.0-1015.16~24.04.2USN-7605-2

linux-oem-6.11Ubuntu

Fixed in:6.11.0-1024.24USN-7606-1

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorLocal

Attack ComplexityHigh

Privileges RequiredLow

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityNone

IntegrityNone

AvailabilityHigh

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

Exploit Intelligence

0.13%probability of exploitation in 30 days

3rdpercentile

Low risk: more likely to be exploited than 3% of all known CVEs.

References

Patch3

Related Vulnerabilities

Other CWE-367 (TOCTOU Race Condition) vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2022-36980	High	8.1	83%	-	Fix
CVE-2024-30088	High	7.0	68%	KEV + Ransom	Fix
CVE-2004-0594	Medium	5.1	55%	-	Fix
CVE-2024-50379	Critical	9.8	44%	-	Fix
CVE-2023-38146	High	8.8	39%	-	Fix
CVE-2024-0132	Critical	9.0	37%	-	Fix

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2025-10-01.