CVE-2025-21967: linux Use After Free
CVSS: 8.8v3.1HighModified
AliasesUBUNTU-CVE-2025-21967DEBIAN-CVE-2025-21967
Published 01-04-2025Last modified 05-08-2026
Vulnerability summary
CVE-2025-21967 is a high (CVSS 8.8) Use After Free vulnerability in linux. EPSS estimates a 0.38% chance of exploitation in the next 30 days, higher than 30.2% of scored vulnerabilities.
CVSS score
8.8/10
010
High · v3.1 (CVE.org)EPSS score
0.38%
0%100%
Low · +0.01 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 20 · Related 18Timeline
- 01-04-2025PublishedVulnerability first disclosed.
- 05-08-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free in ksmbd_free_work_struct ->interim_entry of ksmbd_work could be deleted after oplock is freed. We don't need to manage it with linked list. The interim request could be immediately sent whenever a oplock break wait is needed.
CVSS metrics
5 scores · 4 sources · 2 versionsHigh 7.7Preferred score · OSV · Ubuntu (Ecosystem advisory) · calculated from vector
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NSourcesSingle source
High 8.8Preferred score · CVE.org (CNA)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HSources4 sources · 7.8–8.8
- OSV · UbuntuEcosystem advisory · calculated8.8HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HDiffers
- NVDNIST7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HDiffers
EPSS trend
Probability
0.38%
Chance of exploitation in the next 30 days
Percentile
30%
Versus all other CVEs
30-day change
+0.01 pp
From 0.37% on 19-09-2026
19-09-202619-10-2026
EPSS score0.38%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Ubuntu126 products
- linuxAll versions (No fix recorded) | < 6.8.0-84.84
- linux-allwinner-5.19All versions (No fix recorded)
- linux-awsAll versions (No fix recorded) | < 6.8.0-1039.41
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ 0626e6641f6b467447c81dd7678a69c66f7746cf, < fb776765bfc21d5e4ed03bb3d4406c2b86ff1ac3 | ≥ 0626e6641f6b467447c81dd7678a69c66f7746cf, < 62746ae3f5414244a96293e3b017be637b641280 | ≥ 0626e6641f6b467447c81dd7678a69c66f7746cf, < eb51f6f59d19b92f6fe84d3873f958495ab32f0a | ≥ 0626e6641f6b467447c81dd7678a69c66f7746cf, < bb39ed47065455604729404729d9116868638d31 | 5.15
- linux_kernel≥ 5.15, < 6.6.84 | ≥ 6.7, < 6.12.20 | ≥ 6.13, < 6.13.8 | 6.14:rc1 | 6.14:rc2 | 6.14:rc3 | 6.14:rc4 | 6.14:rc5 | 6.14:rc6
Debian1 product
- linuxAll versions (No fix recorded) | < 6.12.20-1
3 vendors · 129 products
