7.5

CVE-2026-97557: linux

CVSS: 7.5v3.1HighReceived
AliasesUBUNTU-CVE-2026-97557DEBIAN-CVE-2026-97557
Published 25-09-2026Last modified 19-10-2026
Open JSON

Vulnerability summary

CVE-2026-97557 is a high (CVSS 7.5) vulnerability in linux. EPSS estimates a 0.66% chance of exploitation in the next 30 days, higher than 50.7% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
0.66%
0%100%
Low · Change unavailable
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 11 · Related 11
OPENSUSE-SU-2026:12074-1OPENSUSE-SU-2026:22091-1SUSE-SU-2026:24179-1SUSE-SU-2026:24181-1SUSE-SU-2026:24182-1SUSE-SU-2026:24184-1

Timeline

  1. 25-09-2026
    PublishedVulnerability first disclosed.
  2. 19-10-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: smb: client: avoid leaking refcount in cifs_queue_oplock_break() cifs_queue_oplock_break() unconditionally takes a reference on the target file before queueing cifs_oplock_break(). Only that work item decreases the reference counter again. If another oplock break arrives while that work is still queued, queue_work() will return false and not queue this second work item. As a result, we will never reach the point to drop the file reference again and are leaking this reference. This can be triggered when interacting with a slow-responding server. As a result, later unmount operations for this file system will fail with BUG: Dentry ... still in use (1) [unmount of cifs cifs] VFS: Busy inodes after unmount of cifs (cifs) kernel BUG at fs/super.c:777! Fix this by only incrementing the reference count if the work has been queued successfully. Taking it after queue_work() is safe because all three callers hold tcon->open_file_lock across the call and _cifsFileInfo_put() decrements under that same lock, so a worker that starts the handler in the window cannot drop the reference before it has been taken.

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

0.66%

Chance of exploitation in the next 30 days

Percentile

51%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

26-09-202621-10-2026
EPSS score
0.66%

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

Ubuntu168 products
  • linuxAll versions (No fix recorded)
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded)
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian2 products
  • linuxAll versions (No fix recorded) | < 6.1.190-1 | < 6.12.111-1 | < 7.2.7-1
  • linux-6.12< 6.12.111-1~deb12u1
Linux1 product
  • linux≥ b98749cac4a695f084a5ff076f4510b23e353ecd, < 735a3a610136ae10f381d0909dff38e5b5c5f056 | ≥ b98749cac4a695f084a5ff076f4510b23e353ecd, < de2a6bcff2659bea40c7485115b57f0ae189fc01 | ≥ b98749cac4a695f084a5ff076f4510b23e353ecd, < af0193bbf1ac8c0f67f972998b0cc629d6116cf6 | ≥ b98749cac4a695f084a5ff076f4510b23e353ecd, < 2ed2c29dd9593637cfa25ac1eb23241b20202778 | ≥ b98749cac4a695f084a5ff076f4510b23e353ecd, < dfe7b750c7e069873a8a57a11c816831a235618a | ≥ b98749cac4a695f084a5ff076f4510b23e353ecd, < 9f2e63f1b2d5fc5b5423424902c091123e220e7e | 2429fcf06d3cb962693868ab0a927c9038f12a2d | 1ee4f2d7cdcd4508cc3cbe3b2622d7177b89da12 | 53fc31a4853e30d6e8f142b824f724da27ff3e40 | 8092ecc306d81186a64cda42411121f4d35aaff4 | ebac4d0adf68f8962bd82fcf483936edd6ec095b | ≥ 3.16.72, < 3.17 | ≥ 4.9.171, < 4.10 | ≥ 4.14.114, < 4.15 | ≥ 4.19.37, < 4.20 | ≥ 5.0.10, < 5.1 | 5.1

3 vendors · 171 products

References

9 links