5.5

CVE-2025-37999: linux

CVSS: 5.5v3.1MediumAnalyzed
AliasesUBUNTU-CVE-2025-37999DEBIAN-CVE-2025-37999
Published 29-05-2025Last modified 11-05-2026
Open JSON

Vulnerability summary

CVE-2025-37999 is a medium (CVSS 5.5) vulnerability in linux. EPSS estimates a 0.18% chance of exploitation in the next 30 days, higher than 7% of scored vulnerabilities.

Overall risk
22/100
0100
Low · default modelHow is this calculated?
CVSS score
5.5/10
010
Medium · v3.1 (NVD)
EPSS score
0.18%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 3 · Related 3
USN-7699-1USN-7699-2USN-7721-1

Timeline

  1. 29-05-2025
    PublishedVulnerability first disclosed.
  2. 11-05-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: fs/erofs/fileio: call erofs_onlinefolio_split() after bio_add_folio() If bio_add_folio() fails (because it is full), erofs_fileio_scan_folio() needs to submit the I/O request via erofs_fileio_rq_submit() and allocate a new I/O request with an empty `struct bio`. Then it retries the bio_add_folio() call. However, at this point, erofs_onlinefolio_split() has already been called which increments `folio->private`; the retry will call erofs_onlinefolio_split() again, but there will never be a matching erofs_onlinefolio_end() call. This leaves the folio locked forever and all waiters will be stuck in folio_wait_bit_common(). This bug has been added by commit ce63cb62d794 ("erofs: support unencoded inodes for fileio"), but was practically unreachable because there was room for 256 folios in the `struct bio` - until commit 9f74ae8c9ac9 ("erofs: shorten bvecs[] for file-backed mounts") which reduced the array capacity to 16 folios. It was now trivial to trigger the bug by manually invoking readahead from userspace, e.g.: posix_fadvise(fd, 0, st.st_size, POSIX_FADV_WILLNEED); This should be fixed by invoking erofs_onlinefolio_split() only after bio_add_folio() has succeeded. This is safe: asynchronous completions invoking erofs_onlinefolio_end() will not unlock the folio because erofs_fileio_scan_folio() is still holding a reference to be released by erofs_onlinefolio_end() at the end.

CVSS metrics

4 scores · 3 sources · 2 versions

EPSS trend

Probability

0.18%

Chance of exploitation in the next 30 days

Percentile

7%

Versus all other CVEs

30-day change

0.00 pp

From 0.17% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.18%

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

No weakness data has been published for this record.

Affected systems

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≥ ce63cb62d794c98c7631c2296fa845f2a8d0a4a1, < 61e0fc3312309867e5a3495329dad0286d2a5703 | ≥ ce63cb62d794c98c7631c2296fa845f2a8d0a4a1, < c26076197df348c84cc23e5962d61902e072a0f5 | ≥ ce63cb62d794c98c7631c2296fa845f2a8d0a4a1, < bbfe756dc3062c1e934f06e5ba39c239aa953b92 | 6.12
  • linux_kernel≥ 6.12, < 6.12.29 | ≥ 6.13, < 6.14.7 | 6.15:rc1 | 6.15:rc2 | 6.15:rc3 | 6.15:rc4 | 6.15:rc5
Debian1 product
  • linux< 6.12.29-1

3 vendors · 86 products

References

10 links