CVE-2026-80926: Software Security Vulnerability Vulnerability

CRITICAL
Advisory Identifier: GHSA-4r76-cqqc-v36j
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CVSS 9.8
Published
Advisory Summary

CVE-2026-80926 is a CRITICAL (CVSS 9.8) security vulnerability vulnerability (General Security Weakness) affecting Software libraries in the Maven ecosystem. Remediation is available in the latest vendor maintenance releases.

CVE-2026-80926 at a Glance

CVE Identifier CVE-2026-80926
GHSA Identifier GHSA-4r76-cqqc-v36j
Severity CRITICAL
CVSS v3.1 Base Score 9.8
CWE Classification General Security Weakness
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 9.8

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity High (I:H)
Availability High (A:H)

How to Fix CVE-2026-80926

To remediate this vulnerability, upgrade all affected Software dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

mvn dependency:tree

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2026-80926, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree

Analyze the terminal output to locate any version of Software in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than the patched release), your application is affected.

Note: The mvn dependency:tree command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under General Security Weakness. In Software, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free in oplock break notification smb2_oplock_break_noti() reads opinfo->conn without any lock and dereferences it after two allocations which may sleep. When the durable handle owning the oplock is disconnected, session_fd_check() clears opinfo->conn and drops its conn reference under ci->m_lock, and the last ksmbd_conn_put() frees the connection. A break triggered by another connection that races with the teardown can then resurrect the freed connection: ksmbd_conn_get() is a plain atomic_inc, and the queued break work later dereferences the stale conn via ksmbd_conn_write(), a use-after-free reachable by any authenticated client holding a durable batch oplock. Thread the caller's inode into the notification path instead of taking a new reference on it. Every caller of oplock_break() already holds a live ksmbd_file (or an explicit ksmbd_inode_lookup_lock() reference, in the parent lease break paths) on the inode that owns the break target's oplock list, so ci cannot be freed during the call, and its lock can be taken without dereferencing opinfo->o_fp, which a concurrent close may free. Select and pin the connection under ci->m_lock, the same lock session_fd_check() and ksmbd_reopen_durable_fd() use to update opinfo->conn, so a concurrent detach either loses the race to the clear or keeps the connection alive until the notification work releases it. Transfer the reference to the work item and release it on allocation failures.

References

NVD — CVE-2026-80926 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-80926
git.kernel.org/stable/c/0e75389962... WEB
https://git.kernel.org/stable/c/0e753899627b5e28a9fea8bca98262a6f65a2452
git.kernel.org/stable/c/5de0527f78... WEB
https://git.kernel.org/stable/c/5de0527f782430b1109a447646e32033ad018a6a
git.kernel.org/stable/c/892f643b14... WEB
https://git.kernel.org/stable/c/892f643b141aee3f7aa7c0fc61ddcb55c59f1996
git.kernel.org/stable/c/8cc98db4fc... WEB
https://git.kernel.org/stable/c/8cc98db4fc590e6c7d9db6529320982ee16c5d1d
git.kernel.org/stable/c/c8279ae8df... WEB
https://git.kernel.org/stable/c/c8279ae8df68cce9cd3b785e85f7a86c80a46e78

Frequently Asked Questions

What is CVE-2026-80926?
CVE-2026-80926 is a security vulnerability in Software classified as a security vulnerability vulnerability under General Security Weakness.
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2026-80926?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2026-80926?
CVE-2026-80926 has a CVSS v3.1 base score of 9.8 (CRITICAL) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
What CWE is associated with CVE-2026-80926?
CVE-2026-80926 is classified under General Security Weakness.
How can I check Maven dependencies for CVE-2026-80926?
Run the dependency tree command: 'mvn dependency:tree'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-4r76-cqqc-v36j",
  "modified" : "2026-10-03T12:31:05Z",
  "published" : "2026-09-11T21:31:19Z",
  "aliases" : [ "CVE-2026-80926" ],
  "details" : "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix use-after-free in oplock break notification\n\nsmb2_oplock_break_noti() reads opinfo->conn without any lock and\ndereferences it after two allocations which may sleep.  When the\ndurable handle owning the oplock is disconnected, session_fd_check()\nclears opinfo->conn and drops its conn reference under ci->m_lock, and\nthe last ksmbd_conn_put() frees the connection.  A break triggered by\nanother connection that races with the teardown can then resurrect the\nfreed connection: ksmbd_conn_get() is a plain atomic_inc, and the\nqueued break work later dereferences the stale conn via\nksmbd_conn_write(), a use-after-free reachable by any authenticated\nclient holding a durable batch oplock.\n\nThread the caller's inode into the notification path instead of taking\na new reference on it.  Every caller of oplock_break() already holds a\nlive ksmbd_file (or an explicit ksmbd_inode_lookup_lock() reference,\nin the parent lease break paths) on the inode that owns the break\ntarget's oplock list, so ci cannot be freed during the call, and its\nlock can be taken without dereferencing opinfo->o_fp, which a\nconcurrent close may free.  Select and pin the connection under\nci->m_lock, the same lock session_fd_check() and\nksmbd_reopen_durable_fd() use to update opinfo->conn, so a concurrent\ndetach either loses the race to the clear or keeps the connection\nalive until the notification work releases it.  Transfer the reference\nto the work item and release it on allocation failures.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-80926"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/0e753899627b5e28a9fea8bca98262a6f65a2452"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/5de0527f782430b1109a447646e32033ad018a6a"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/892f643b141aee3f7aa7c0fc61ddcb55c59f1996"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/8cc98db4fc590e6c7d9db6529320982ee16c5d1d"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/c8279ae8df68cce9cd3b785e85f7a86c80a46e78"
  } ],
  "database_specific" : {
    "cwe_ids" : [ ],
    "severity" : "CRITICAL",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-09-11T20:18:56Z"
  }
}