CVE-2026-97556: linux

CVSS: UnknownReceived
AliasesUBUNTU-CVE-2026-97556DEBIAN-CVE-2026-97556
Published 25-09-2026Last modified 19-10-2026
Open JSON

Vulnerability summary

CVE-2026-97556 is a vulnerability in linux with no CVSS score yet. EPSS estimates a 0.21% chance of exploitation in the next 30 days, higher than 10% of scored vulnerabilities.

Overall risk
0/100
0100
Minimal · default modelHow is this calculated?
CVSS score
Not scored
010
No CVSS score recorded
EPSS score
0.21%
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 1 · Related 1
OPENSUSE-SU-2026:12074-1

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 when cifs_sb_tlink() fails cifs_oplock_break() takes over the reference that cifs_queue_oplock_break() acquired when it queued the work, and drops it with _cifsFileInfo_put() once the break has been processed. Only in setups with "-o multiuser", cifs_sb_tlink() may fail, at which point cifs_oplock_break() returns without putting the file reference, mirroring the reference leak we already fixed in the companion patch to cifs_queue_oplock_break(). This would trigger a crash due to busy inodes on the next unmount: BUG: Dentry ... still in use (1) [unmount of cifs cifs] VFS: Busy inodes after unmount of cifs (cifs) Drop the reference on that path as well. Doing so before the out label mirrors the normal path, which also puts the reference before cifs_done_oplock_break(). Found by Sashiko code review. The failure path was not exercised at runtime.

CVSS metrics

Risk metrics not yet published.

EPSS trend

Probability

0.21%

Chance of exploitation in the next 30 days

Percentile

10%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

26-09-202621-10-2026
EPSS score
0.21%

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

Ubuntu157 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≥ 5ee28bcfbaacf289eb25c662a2862542ea6ce6a7, < 55c5f095d4df14271b238f826e1392fda7b6e60e | ≥ e8f5f849ffce24490eb9449e98312b66c0dba76f, < e9c5bcc88b8337157e480c85a6d2f326bc265012 | ≥ e8f5f849ffce24490eb9449e98312b66c0dba76f, < 9ec991e148368e3207e98134c509a625097f7693 | ≥ e8f5f849ffce24490eb9449e98312b66c0dba76f, < dd03fd658ea59821505e0e643b6b7cbdf51c4e1d | ≥ e8f5f849ffce24490eb9449e98312b66c0dba76f, < 1d1b0f1d812a4011a57bc6c70492c34a2e46c6dd | ≥ e8f5f849ffce24490eb9449e98312b66c0dba76f, < 23b26f4408ac3f35a482d2e5cf6fc865d4201b71 | b99f490ea87ebcca3a429fd8837067feb56a4c7c | 6b67a6d2e50634fe127e656147c81915955e9f5e | ≥ 6.1.47, < 6.1.189 | ≥ 5.15.128, < 5.16 | ≥ 6.4.12, < 6.5 | 6.5

3 vendors · 160 products

References

9 links