What is CVE-2025-21988?

CVE-2025-21988 is a critical-severity vulnerability in Linux. CVSS score: 9.8/10. Published 2025-04-02.

How severe is CVE-2025-21988?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2025-21988 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Vulnerability in Linux

CVE-2025-21988

In the Linux kernel, the following vulnerability has been resolved: fs/netfs/read_collect: add to next->prev_donated If multiple subrequests donate data to the same "next" request (depending on the subrequest completion order), each of them would overwrite the `prev_donated` field, causing data corruption and a BUG() crash ("Can't donate prior to front").

EPSS: 0.002 (7.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Linux — versions ee4cdf7ba857a894ad1650d6ab77669cbbfa329e, 6.12, 0
Linux Linux_kernel

Public proof-of-concept exploits

fkie-cad/nvd-json-data-feeds

References

416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)

Frequently asked questions

What is CVE-2025-21988?: CVE-2025-21988 is a critical-severity vulnerability in Linux. CVSS score: 9.8/10. Published 2025-04-02.
How severe is CVE-2025-21988?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2025-21988 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.