5.7

CVE-2026-97558: linux

CVSS: 5.7v4.0MediumReceived
AliasesUBUNTU-CVE-2026-97558DEBIAN-CVE-2026-97558
Published 25-09-2026Last modified 21-10-2026

Vulnerability summary

CVE-2026-97558 is a medium (CVSS 5.7) vulnerability in linux. EPSS estimates a 0.21% chance of exploitation in the next 30 days, higher than 11.2% of scored vulnerabilities.

Overall risk
23/100
0100
Low · default modelHow is this calculated?
CVSS score
5.7/10
010
Medium · v4.0 (OSV · Ubuntu), selected by version preference
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

Timeline

  1. 25-09-2026
    PublishedVulnerability first disclosed.
  2. 21-10-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix cifsFileInfo reference leak in deferred close When cifs_close() defers a close, it hands the cifsFileInfo reference of the closing struct file to the queued work. Each execution of smb2_deferred_work_close() drops one such reference. deferred_close_scheduled can be false while the work is pending: the workqueue clears PENDING when the callback starts to run, before the callback clears the flag under deferred_lock. A close in that interval requeues the running work, and the callback then clears the flag, leaving the requeued work pending with the flag down. A later cifs_open() can reuse the handle and its cifs_close() reaches the same branch: queue_delayed_work() fails because the work is still pending, but cifs_close() returns without dropping the closing file's reference. The cifsFileInfo count stays pinned and its tlink, dentry and server handle are leaked. Check the return value and hand off the reference only when work was actually queued. Otherwise, use the shared _cifsFileInfo_put(), like the mod_delayed_work() branch above: the pending execution already owns its reference. This issue was found by an in-house static analysis tool.

CVSS metrics

1 score · 1 source · 1 version

EPSS trend

Probability

0.21%

Chance of exploitation in the next 30 days

Percentile

11%

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)
Debian1 product
  • linuxAll versions (No fix recorded) | < 6.12.113-1 | < 7.2.7-1
Linux1 product
  • linux≥ c3f207ab29f793b8c942ce8067ed123f18d5b81b, < 525c225e23d61694091f2806de553a69362a78ff | ≥ c3f207ab29f793b8c942ce8067ed123f18d5b81b, < bbeb7a42c9ea656e17ddcbdc2d7917aa853383a6 | ≥ c3f207ab29f793b8c942ce8067ed123f18d5b81b, < a6767712902beb0f53238be485971c9a83ea1079 | ≥ c3f207ab29f793b8c942ce8067ed123f18d5b81b, < ea93759d6c2789924f4e557aed5be532207715ea | ≥ c3f207ab29f793b8c942ce8067ed123f18d5b81b, < 5520e89a5a4f834bced64cf2ac927001cc513a40 | 5.13

3 vendors · 159 products

References

8 links