7.8

CVE-2025-21811: linux Use After Free

CVSS: 7.8v3.1HighModified
AliasesUBUNTU-CVE-2025-21811DEBIAN-CVE-2025-21811
Published 27-02-2025Last modified 05-08-2026
Open JSON

Vulnerability summary

CVE-2025-21811 is a high (CVSS 7.8) Use After Free vulnerability in linux. EPSS estimates a 0.26% chance of exploitation in the next 30 days, higher than 16% of scored vulnerabilities.

Overall risk
31/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.8/10
010
High · v3.1 (CVE.org)
EPSS score
0.26%
0%100%
Low · +0.01 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 51 · Related 50
DLA-4102-1DLA-4178-1USN-7510-1USN-7510-2USN-7510-3USN-7510-4

Timeline

  1. 27-02-2025
    PublishedVulnerability first disclosed.
  2. 05-08-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: nilfs2: protect access to buffers with no active references nilfs_lookup_dirty_data_buffers(), which iterates through the buffers attached to dirty data folios/pages, accesses the attached buffers without locking the folios/pages. For data cache, nilfs_clear_folio_dirty() may be called asynchronously when the file system degenerates to read only, so nilfs_lookup_dirty_data_buffers() still has the potential to cause use after free issues when buffers lose the protection of their dirty state midway due to this asynchronous clearing and are unintentionally freed by try_to_free_buffers(). Eliminate this race issue by adjusting the lock section in this function.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.26%

Chance of exploitation in the next 30 days

Percentile

16%

Versus all other CVEs

30-day change

+0.01 pp

From 0.25% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.26%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Ubuntu136 products
  • linuxAll versions (No fix recorded) | < 4.4.0-276.310 | < 4.15.0-245.257 | < 5.4.0-216.236 | < 5.15.0-140.150 | < 6.8.0-64.67
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-aws< 4.4.0-1150.156 | < 4.4.0-1188.203 | < 4.15.0-1187.200 | < 5.4.0-1146.156 | < 5.15.0-1084.91 | < 6.8.0-1032.34
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux2 products
  • linux≥ 8c26c4e2694a163d525976e804d81cd955bbb40c, < e1fc4a90a90ea8514246c45435662531975937d9 | ≥ 8c26c4e2694a163d525976e804d81cd955bbb40c, < 72cf688d0ce7e642b12ddc9b2a42524737ec1b4a | ≥ 8c26c4e2694a163d525976e804d81cd955bbb40c, < d8ff250e085a4c4cdda4ad1cdd234ed110393143 | ≥ 8c26c4e2694a163d525976e804d81cd955bbb40c, < 58c27fa7a610b6e8d44e6220e7dbddfbaccaf439 | ≥ 8c26c4e2694a163d525976e804d81cd955bbb40c, < 8e1b9201c9a24638cf09c6e1c9f224157328010b | ≥ 8c26c4e2694a163d525976e804d81cd955bbb40c, < 4b08d23d7d1917bef4fbee8ad81372f49b006656 | ≥ 8c26c4e2694a163d525976e804d81cd955bbb40c, < c437dfac9f7a5a46ac2a5e6d6acd3059e9f68188 | ≥ 8c26c4e2694a163d525976e804d81cd955bbb40c, < 367a9bffabe08c04f6d725032cce3d891b2b9e1a | 3.10
  • linux_kernel≥ 3.10, < 5.4.291 | ≥ 5.5, < 5.10.235 | ≥ 5.11, < 5.15.179 | ≥ 5.16, < 6.1.129 | ≥ 6.2, < 6.6.76 | ≥ 6.7, < 6.12.13 | ≥ 6.13, < 6.13.2
Debian1 product
  • linux< 6.1.129-1 | < 6.12.13-1

3 vendors · 139 products

References

64 links
Show all 64 references