CVE-2026-45856: Software Security Vulnerability Vulnerability

HIGH
Advisory Identifier: GHSA-xq3r-74hw-4c5p
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CVSS 7.1
CWE-125
Published
Advisory Summary

CVE-2026-45856 is a HIGH (CVSS 7.1) security vulnerability vulnerability (CWE-125: Out-of-bounds Read) affecting Software libraries in the Maven ecosystem. The weakness occurs when the product reads data past the end, or before the beginning, of the intended buffer.. Remediation is available in the latest vendor maintenance releases.

CVE-2026-45856 at a Glance

CVE Identifier CVE-2026-45856
GHSA Identifier GHSA-xq3r-74hw-4c5p
Severity HIGH
CVSS v3.1 Base Score 7.1
CWE Classification CWE-125: Out-of-bounds Read
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 7.1

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:N/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 None (I:N)
Availability High (A:H)

How to Fix CVE-2026-45856

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-2026-45856, 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 CWE-125: Out-of-bounds Read, where the product reads data past the end, or before the beginning, of the intended buffer. 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: RDMA/uverbs: Validate wqe_size before using it in ib_uverbs_post_send ib_uverbs_post_send() uses cmd.wqe_size from userspace without any validation before passing it to kmalloc() and using the allocated buffer as struct ib_uverbs_send_wr. If a user provides a small wqe_size value (e.g., 1), kmalloc() will succeed, but subsequent accesses to user_wr->opcode, user_wr->num_sge, and other fields will read beyond the allocated buffer, resulting in an out-of-bounds read from kernel heap memory. This could potentially leak sensitive kernel information to userspace. Additionally, providing an excessively large wqe_size can trigger a WARNING in the memory allocation path, as reported by syzkaller. This is inconsistent with ib_uverbs_unmarshall_recv() which properly validates that wqe_size >= sizeof(struct ib_uverbs_recv_wr) before proceeding. Add the same validation for ib_uverbs_post_send() to ensure wqe_size is at least sizeof(struct ib_uverbs_send_wr).

References

NVD — CVE-2026-45856 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-45856
git.kernel.org/stable/c/01c9b15264... WEB
https://git.kernel.org/stable/c/01c9b152647dc70dc06a4a2eff86ebb3b3c76075
git.kernel.org/stable/c/1956f0a74c... WEB
https://git.kernel.org/stable/c/1956f0a74ccf5dc9c3ef717f2985c3ed3400aab0
git.kernel.org/stable/c/9b5ac1c153... WEB
https://git.kernel.org/stable/c/9b5ac1c15334d46c0dbd49d64a2257b929500163
git.kernel.org/stable/c/9c15ec4cd4... WEB
https://git.kernel.org/stable/c/9c15ec4cd4e7f57c6bbcb4e73e99290f150dd2a7
git.kernel.org/stable/c/bef70ff984... WEB
https://git.kernel.org/stable/c/bef70ff9841990658610512b4a18e4a88c9b4df6
git.kernel.org/stable/c/bf1feed1a7... WEB
https://git.kernel.org/stable/c/bf1feed1a7886af945f92890493aefd2b5c9928a
git.kernel.org/stable/c/bf4454da8b... WEB
https://git.kernel.org/stable/c/bf4454da8b1e712714628c0a0d6e7845bb40790a
git.kernel.org/stable/c/d533425ac1... WEB
https://git.kernel.org/stable/c/d533425ac1f2925b4fc3e4ed9b9d72362cb23475

Frequently Asked Questions

What is CVE-2026-45856?
CVE-2026-45856 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-125: Out-of-bounds Read.
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2026-45856?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2026-45856?
CVE-2026-45856 has a CVSS v3.1 base score of 7.1 (HIGH) with vector string CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H.
What CWE is associated with CVE-2026-45856?
CVE-2026-45856 is classified under CWE-125: Out-of-bounds Read (The product reads data past the end, or before the beginning, of the intended buffer.).
How can I check Maven dependencies for CVE-2026-45856?
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-xq3r-74hw-4c5p",
  "modified" : "2026-05-30T12:30:23Z",
  "published" : "2026-05-27T15:33:13Z",
  "aliases" : [ "CVE-2026-45856" ],
  "details" : "In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/uverbs: Validate wqe_size before using it in ib_uverbs_post_send\n\nib_uverbs_post_send() uses cmd.wqe_size from userspace without any\nvalidation before passing it to kmalloc() and using the allocated\nbuffer as struct ib_uverbs_send_wr.\n\nIf a user provides a small wqe_size value (e.g., 1), kmalloc() will\nsucceed, but subsequent accesses to user_wr->opcode, user_wr->num_sge,\nand other fields will read beyond the allocated buffer, resulting in\nan out-of-bounds read from kernel heap memory. This could potentially\nleak sensitive kernel information to userspace.\n\nAdditionally, providing an excessively large wqe_size can trigger a\nWARNING in the memory allocation path, as reported by syzkaller.\n\nThis is inconsistent with ib_uverbs_unmarshall_recv() which properly\nvalidates that wqe_size >= sizeof(struct ib_uverbs_recv_wr) before\nproceeding.\n\nAdd the same validation for ib_uverbs_post_send() to ensure wqe_size\nis at least sizeof(struct ib_uverbs_send_wr).",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H"
  } ],
  "affected" : [ ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-45856"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/01c9b152647dc70dc06a4a2eff86ebb3b3c76075"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/1956f0a74ccf5dc9c3ef717f2985c3ed3400aab0"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/9b5ac1c15334d46c0dbd49d64a2257b929500163"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/9c15ec4cd4e7f57c6bbcb4e73e99290f150dd2a7"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/bef70ff9841990658610512b4a18e4a88c9b4df6"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/bf1feed1a7886af945f92890493aefd2b5c9928a"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/bf4454da8b1e712714628c0a0d6e7845bb40790a"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/d533425ac1f2925b4fc3e4ed9b9d72362cb23475"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-125" ],
    "severity" : "HIGH",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-05-27T14:16:57Z"
  }
}