What is CVE-2025-39779?

CVE-2025-39779 is a medium-severity vulnerability in Linux. CVSS score: 5.5/10. Published 2025-09-11.

How severe is CVE-2025-39779?

Medium severity. CVSS v3 base score is 5.5 out of 10.

Is CVE-2025-39779 known to be exploited?

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

Vulnerability in Linux

CVE-2025-39779

In the Linux kernel, the following vulnerability has been resolved: btrfs: subpage: keep TOWRITE tag until folio is cleaned btrfs_subpage_set_writeback() calls folio_start_writeback() the first time a folio is written back, and it also c…

EPSS: 0.001 (3.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

Affected products

Linux — versions 3470da3b7d87fde4b9729d4e29c2dc074cd59c10, 5.13, 0
Linux Linux_kernel — versions 6.17

Public proof-of-concept exploits

w4zu/Debian_

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-2025-39779?: CVE-2025-39779 is a medium-severity vulnerability in Linux. CVSS score: 5.5/10. Published 2025-09-11.
How severe is CVE-2025-39779?: Medium severity. CVSS v3 base score is 5.5 out of 10.
Is CVE-2025-39779 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.