CVE-2025-21998: firmware: qcom: uefisecapp: fix efivars registration race
Vulnerability summary
CVE-2025-21998 is a medium (CVSS 4.7) vulnerability in linux. EPSS estimates a 0.14% chance of exploitation in the next 30 days, higher than 3.4% of scored vulnerabilities.
Not severe (CVSS 4.7, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 4 · Related 4Timeline
- 03-04-2025PublishedVulnerability first disclosed.
- 11-05-2026Last modifiedVulnerability information updated.
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.
CVSS metrics
4 scores · 4 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated4.7MediumCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated4.7MediumCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
- NVDNIST4.7MediumCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.14%
Chance of exploitation in the next 30 days
Percentile
3%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.14% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-367Time-of-check Time-of-use (TOCTOU) Race ConditionThe product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check.
- CWE-476NULL Pointer DereferenceThe product dereferences a pointer that it expects to be valid but is NULL.
Affected systems
Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu83 products
- linux-allwinner-5.19All versions (No fix recorded)
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
- linux-aws-5.13All versions (No fix recorded)
- linux-aws-5.19All versions (No fix recorded)
Linux2 products
- linux≥ 6612103ec35af6058bb85ab24dae28e119b3c055, < c4e37b381a7a243c298a4858fc0a5a74e737c79a | ≥ 6612103ec35af6058bb85ab24dae28e119b3c055, < f15a2b96a0e41c426c63a932d0e63cde7b9784aa | ≥ 6612103ec35af6058bb85ab24dae28e119b3c055, < da8d493a80993972c427002684d0742560f3be4a | 6.11
- linux_kernel≥ 6.11, < 6.12.21 | ≥ 6.13, < 6.13.9 | 6.14:rc1 | 6.14:rc2 | 6.14:rc3 | 6.14:rc4 | 6.14:rc5 | 6.14:rc6 | 6.14:rc7
Debian1 product
- linux< 6.12.21-1
3 vendors · 86 products
