CVE-2026-89655: Software Security Vulnerability Vulnerability

CRITICAL
Advisory Identifier: GHSA-67r3-hj2c-67vv
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CVSS 9.8
Published
Advisory Summary

CVE-2026-89655 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-2026-89655 at a Glance

CVE Identifier CVE-2026-89655
GHSA Identifier GHSA-67r3-hj2c-67vv
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-2026-89655

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-2026-89655, 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: ceph: fix UAF in __kick_flushing_caps() on cf entry freed during unlock list_for_each_entry() iterates ci->i_cap_flush_list but drops i_ceph_lock to send cap messages. During the unlock window, handle_cap_flush_ack() can acquire i_ceph_lock, detach cf entries with tid <= flush_tid from the list, release i_ceph_lock, and free them via ceph_free_cap_flush() outside any lock. When the original thread reacquires i_ceph_lock and the for-loop macro advances via cf = list_next_entry(cf, i_list), it dereferences cf->i_list.next on freed memory. The race timeline: __kick_flushing_caps() handle_cap_flush_ack() ----------------------- ----------------------- holds i_ceph_lock <--- iterates to cf (tid=10) prepares FLUSH message drops i_ceph_lock <--- __send_cap() ── FLUSH(tid=10) MDS sends FLUSH_ACK(tid=10) ---> acquires i_ceph_lock cf->tid(10) <= flush_tid(10), detaches cf from i_cap_flush_list drops i_ceph_lock ceph_free_cap_flush(cf) <- frees it! acquires i_ceph_lock <--- for-loop advances: cf = list_next_entry(cf, i_list) -- UAF on freed cf->i_list.next The cf was just sent by __kick_flushing_caps itself via __send_cap(). The MDS may respond with FLUSH_ACK quickly enough that handle_cap_flush_ack() frees cf before __kick_flushing_caps can finish the iteration. Fix by converting to a manual while loop: save the next pointer under i_ceph_lock before dropping it, then use the saved pointer after reacquiring, so the potentially-freed cf is never accessed again.

References

NVD — CVE-2026-89655 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-89655
git.kernel.org/stable/c/0154243008... WEB
https://git.kernel.org/stable/c/01542430081014d80fc9e70e92d6647432ddb7fc
git.kernel.org/stable/c/091137821e... WEB
https://git.kernel.org/stable/c/091137821e1fc88f37e15201abf055c9494ddc61
git.kernel.org/stable/c/19f16f04c2... WEB
https://git.kernel.org/stable/c/19f16f04c2b014a7dd214dc1e42557d8530b16f3
git.kernel.org/stable/c/23eb34a53a... WEB
https://git.kernel.org/stable/c/23eb34a53a53cb1a6dab1eeee830633207ac158d
git.kernel.org/stable/c/2701431aa3... WEB
https://git.kernel.org/stable/c/2701431aa3cc8b23efe6890182e7b04f5e76fab5
git.kernel.org/stable/c/2dba24dcd5... WEB
https://git.kernel.org/stable/c/2dba24dcd5050be4b7b119e6f0b01f62203b5d26
git.kernel.org/stable/c/7af4c4f013... WEB
https://git.kernel.org/stable/c/7af4c4f01305b0935adf6d4301b1ec407025485d
git.kernel.org/stable/c/fe46746087... WEB
https://git.kernel.org/stable/c/fe46746087b5b9c5bb2d022df6c7819218494ced

Frequently Asked Questions

What is CVE-2026-89655?
CVE-2026-89655 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-2026-89655?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2026-89655?
CVE-2026-89655 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-2026-89655?
CVE-2026-89655 is classified under General Security Weakness.
How can I check Maven dependencies for CVE-2026-89655?
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-67r3-hj2c-67vv",
  "modified" : "2026-09-14T15:32:33Z",
  "published" : "2026-09-11T21:31:35Z",
  "aliases" : [ "CVE-2026-89655" ],
  "details" : "In the Linux kernel, the following vulnerability has been resolved:\n\nceph: fix UAF in __kick_flushing_caps() on cf entry freed during unlock\n\nlist_for_each_entry() iterates ci->i_cap_flush_list but drops\ni_ceph_lock to send cap messages.  During the unlock window,\nhandle_cap_flush_ack() can acquire i_ceph_lock, detach cf entries\nwith tid <= flush_tid from the list, release i_ceph_lock, and free\nthem via ceph_free_cap_flush() outside any lock.  When the original\nthread reacquires i_ceph_lock and the for-loop macro advances via\ncf = list_next_entry(cf, i_list), it dereferences cf->i_list.next\non freed memory.\n\nThe race timeline:\n\n  __kick_flushing_caps()              handle_cap_flush_ack()\n  -----------------------             -----------------------\n  holds i_ceph_lock        <---\n  iterates to cf (tid=10)\n  prepares FLUSH message\n  drops i_ceph_lock        <---\n  __send_cap() ── FLUSH(tid=10)\n\t                              MDS sends FLUSH_ACK(tid=10)\n                           --->       acquires i_ceph_lock\n                                      cf->tid(10) <= flush_tid(10),\n                                      detaches cf from i_cap_flush_list\n                                      drops i_ceph_lock\n                                      ceph_free_cap_flush(cf) <- frees it!\n  acquires i_ceph_lock     <---\n  for-loop advances:\n    cf = list_next_entry(cf, i_list)\n      -- UAF on freed cf->i_list.next\n\nThe cf was just sent by __kick_flushing_caps itself via __send_cap().\nThe MDS may respond with FLUSH_ACK quickly enough that\nhandle_cap_flush_ack() frees cf before __kick_flushing_caps can\nfinish the iteration.\n\nFix by converting to a manual while loop: save the next pointer\nunder i_ceph_lock before dropping it, then use the saved pointer\nafter reacquiring, so the potentially-freed cf is never accessed again.",
  "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-2026-89655"
  }, {
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    "url" : "https://git.kernel.org/stable/c/01542430081014d80fc9e70e92d6647432ddb7fc"
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    "url" : "https://git.kernel.org/stable/c/091137821e1fc88f37e15201abf055c9494ddc61"
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  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/23eb34a53a53cb1a6dab1eeee830633207ac158d"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/2701431aa3cc8b23efe6890182e7b04f5e76fab5"
  }, {
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    "url" : "https://git.kernel.org/stable/c/2dba24dcd5050be4b7b119e6f0b01f62203b5d26"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/7af4c4f01305b0935adf6d4301b1ec407025485d"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/fe46746087b5b9c5bb2d022df6c7819218494ced"
  } ],
  "database_specific" : {
    "cwe_ids" : [ ],
    "severity" : "CRITICAL",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-09-11T20:19:51Z"
  }
}