CVE-2026-89903: Software Security Vulnerability Vulnerability

HIGH
Advisory Identifier: GHSA-fx3m-r2wg-wx6v
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CVSS 7.8
Published
Advisory Summary

CVE-2026-89903 is a HIGH (CVSS 7.8) security vulnerability vulnerability (General Security Weakness) affecting Software libraries in the Maven ecosystem. Remediation is available in the latest vendor maintenance releases.

CVE-2026-89903 at a Glance

CVE Identifier CVE-2026-89903
GHSA Identifier GHSA-fx3m-r2wg-wx6v
Severity HIGH
CVSS v3.1 Base Score 7.8
CWE Classification General Security Weakness
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 7.8

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

Attack Vector Local (AV:L)
Attack Complexity Low (AC:L)
Privileges Required Low (PR:L)
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-2026-89903

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-2026-89903, 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: LoongArch: Do not save/restore percpu base register in rethook trampoline The rethook trampoline saves $r21 ($u0), the percpu base, into its frame at entry and restores it at exit. Inbetween rethook_trampoline_handler() may schedule via preempt_enable_notrace(). If the task migrates to another CPU, the frame's $r21 holds the old CPU's percpu base, and restoring it poisons $r21 on the new CPU. Until the next user->kernel transition heals $r21, all this_cpu_*() accesses (runqueues, RCU per-CPU data, timer tick programming, FPU ownership) hit the wrong CPU's percpu area. Under kretprobe-heavy preemptible load this can corrupt scheduler and timer state: scheduling-while-atomic splats, wrong-CPU RCU warnings, WARN_ON_ONCE(rq != this_rq()) in nohz_balance_exit_idle(), and CPUs parking in the idle loop with the constant timer never re-armed (hard lockup). Reproduces on a Loongson-3A6000 with kretprobes on VFS paths plus heavy file churn (OS install / unsquashfs). By convention $r21 always holds the current CPU's percpu base in kernel mode: SAVE_SOME() at exception entry reloads it only when coming from user mode, and RESTORE_SOME() restores it only when returning to user mode; the context-switch path never writes it. Therefore the live $r21 at trampoline exit is already correct, and nothing inbetween can change it legitimately (kernel C code cannot write a global register variable). The same flaw existed even in the pre-rethook kretprobe trampoline since v6.3; it was carried over when rethook replaced it. Drop both the save and the restore here. Drop the restore is enough to solve the issue, and drop the save is to keep the code tidy and no need to clear it.

References

NVD — CVE-2026-89903 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-89903
git.kernel.org/stable/c/266ffc92e6... WEB
https://git.kernel.org/stable/c/266ffc92e68593759adfe3d58f188773d32782c3
git.kernel.org/stable/c/8f15e95b43... WEB
https://git.kernel.org/stable/c/8f15e95b438bc6b3c9f23a33c9a0d0678ebd1dc8
git.kernel.org/stable/c/a03b5e7483... WEB
https://git.kernel.org/stable/c/a03b5e7483ad2c33ba5dd2adb8552e84bfee8fe2
git.kernel.org/stable/c/c048b0a3c0... WEB
https://git.kernel.org/stable/c/c048b0a3c0836c4b1bef4b51d355d27090bf6790
git.kernel.org/stable/c/c3f2feace5... WEB
https://git.kernel.org/stable/c/c3f2feace5e4f4b01b68b9f947b19adb4155c32e

Frequently Asked Questions

What is CVE-2026-89903?
CVE-2026-89903 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-2026-89903?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2026-89903?
CVE-2026-89903 has a CVSS v3.1 base score of 7.8 (HIGH) with vector string CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
What CWE is associated with CVE-2026-89903?
CVE-2026-89903 is classified under General Security Weakness.
How can I check Maven dependencies for CVE-2026-89903?
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-fx3m-r2wg-wx6v",
  "modified" : "2026-09-16T15:31:01Z",
  "published" : "2026-09-16T12:30:41Z",
  "aliases" : [ "CVE-2026-89903" ],
  "details" : "In the Linux kernel, the following vulnerability has been resolved:\n\nLoongArch: Do not save/restore percpu base register in rethook trampoline\n\nThe rethook trampoline saves $r21 ($u0), the percpu base, into its frame\nat entry and restores it at exit. Inbetween rethook_trampoline_handler()\nmay schedule via preempt_enable_notrace().\n\nIf the task migrates to another CPU, the frame's $r21 holds the old\nCPU's percpu base, and restoring it poisons $r21 on the new CPU. Until\nthe next user->kernel transition heals $r21, all this_cpu_*() accesses\n(runqueues, RCU per-CPU data, timer tick programming, FPU ownership)\nhit the wrong CPU's percpu area.\n\nUnder kretprobe-heavy preemptible load this can corrupt scheduler and\ntimer state: scheduling-while-atomic splats, wrong-CPU RCU warnings,\nWARN_ON_ONCE(rq != this_rq()) in nohz_balance_exit_idle(), and CPUs\nparking in the idle loop with the constant timer never re-armed (hard\nlockup). Reproduces on a Loongson-3A6000 with kretprobes on VFS paths\nplus heavy file churn (OS install / unsquashfs).\n\nBy convention $r21 always holds the current CPU's percpu base in kernel\nmode: SAVE_SOME() at exception entry reloads it only when coming from\nuser mode, and RESTORE_SOME() restores it only when returning to user\nmode; the context-switch path never writes it. Therefore the live $r21\nat trampoline exit is already correct, and nothing inbetween can change\nit legitimately (kernel C code cannot write a global register variable).\nThe same flaw existed even in the pre-rethook kretprobe trampoline since\nv6.3; it was carried over when rethook replaced it. Drop both the save\nand the restore here. Drop the restore is enough to solve the issue, and\ndrop the save is to keep the code tidy and no need to clear it.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-89903"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/266ffc92e68593759adfe3d58f188773d32782c3"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/8f15e95b438bc6b3c9f23a33c9a0d0678ebd1dc8"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/a03b5e7483ad2c33ba5dd2adb8552e84bfee8fe2"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/c048b0a3c0836c4b1bef4b51d355d27090bf6790"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/c3f2feace5e4f4b01b68b9f947b19adb4155c32e"
  } ],
  "database_specific" : {
    "cwe_ids" : [ ],
    "severity" : "HIGH",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-09-16T11:16:59Z"
  }
}