CVE-2026-89563: Software Security Vulnerability Vulnerability

HIGH
Advisory Identifier: GHSA-7pg6-vmqr-62jx
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CVSS 7.8
Published
Advisory Summary

CVE-2026-89563 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-2026-89563 at a Glance

CVE Identifier CVE-2026-89563
GHSA Identifier GHSA-7pg6-vmqr-62jx
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-2026-89563

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-2026-89563, 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: ip6_tunnel: use skb_cow_head() in ip6_tnl_xmit() ip6_tnl_xmit() may need to expand headroom before it can push the outer IPv6 and optional encap headers. It currently does that with skb_realloc_headroom(), copies skb->sk ownership, consumes the original skb, and then continues processing with the replacement skb kept only in its local variable. That is safe only if the helper cannot fail afterwards. But this helper still has post-reallocation error exits. collect_md tunnels reject non-NONE encap after the replacement, and ip6_tnl_encap() can also fail later. In those cases the helper returns an error to its callers while the caller still only has the original skb pointer. Both ip6_tnl_start_xmit() and the IPv6 GRE paths free the caller skb on error, so they can end up freeing an skb that ip6_tnl_xmit() already consumed. Use skb_cow_head() instead. It provides the required headroom and writability without privately replacing the caller-owned skb, so later error returns cannot leave callers with a stale pointer. The Ethernet users, ip6gretap and ip6erspan, clear IFF_TX_SKB_SHARING and already call skb_cow_head() before entering ip6_tnl_xmit(). They do not rely on the removed skb_shared() reallocation. This also makes the IPv6 tunnel path consistent with ip_tunnel_xmit().

References

NVD — CVE-2026-89563 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-89563
git.kernel.org/stable/c/37df5bc6b5... WEB
https://git.kernel.org/stable/c/37df5bc6b5ccad88c2faa0f5466f150178882b74
git.kernel.org/stable/c/629d5557e6... WEB
https://git.kernel.org/stable/c/629d5557e635cdbc109a14ed913ba5a540e3f79a
git.kernel.org/stable/c/6e8eff8ed1... WEB
https://git.kernel.org/stable/c/6e8eff8ed13b14708bc39f170144eacde494aac6
git.kernel.org/stable/c/87f21b59dd... WEB
https://git.kernel.org/stable/c/87f21b59ddc618eff9670c174842964ad65fdade
git.kernel.org/stable/c/8fc56ca49f... WEB
https://git.kernel.org/stable/c/8fc56ca49fc0ee1725b55c67bb43ab0dd01f3f52
git.kernel.org/stable/c/b36dfd6e8c... WEB
https://git.kernel.org/stable/c/b36dfd6e8cff00cea81c11cc0af88d1564763461
git.kernel.org/stable/c/dc1a319a48... WEB
https://git.kernel.org/stable/c/dc1a319a4815c074914e2812e0e9cd0164ca682b
git.kernel.org/stable/c/defa0adeff... WEB
https://git.kernel.org/stable/c/defa0adeff132cc90ed66915b9a104d9393e1e54

Frequently Asked Questions

What is CVE-2026-89563?
CVE-2026-89563 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-2026-89563?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2026-89563?
CVE-2026-89563 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-2026-89563?
CVE-2026-89563 is classified under General Security Weakness.
How can I check Maven dependencies for CVE-2026-89563?
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-7pg6-vmqr-62jx",
  "modified" : "2026-09-14T15:32:29Z",
  "published" : "2026-09-11T21:31:32Z",
  "aliases" : [ "CVE-2026-89563" ],
  "details" : "In the Linux kernel, the following vulnerability has been resolved:\n\nip6_tunnel: use skb_cow_head() in ip6_tnl_xmit()\n\nip6_tnl_xmit() may need to expand headroom before it can push the\nouter IPv6 and optional encap headers. It currently does that with\nskb_realloc_headroom(), copies skb->sk ownership, consumes the original\nskb, and then continues processing with the replacement skb kept only in\nits local variable.\n\nThat is safe only if the helper cannot fail afterwards. But this helper\nstill has post-reallocation error exits. collect_md tunnels reject\nnon-NONE encap after the replacement, and ip6_tnl_encap() can also fail\nlater. In those cases the helper returns an error to its callers while\nthe caller still only has the original skb pointer.\n\nBoth ip6_tnl_start_xmit() and the IPv6 GRE paths free the caller skb on\nerror, so they can end up freeing an skb that ip6_tnl_xmit() already\nconsumed.\n\nUse skb_cow_head() instead. It provides the required headroom and\nwritability without privately replacing the caller-owned skb, so later\nerror returns cannot leave callers with a stale pointer.\n\nThe Ethernet users, ip6gretap and ip6erspan, clear IFF_TX_SKB_SHARING\nand already call skb_cow_head() before entering ip6_tnl_xmit(). They do\nnot rely on the removed skb_shared() reallocation. This also makes the\nIPv6 tunnel path consistent with ip_tunnel_xmit().",
  "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-2026-89563"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/37df5bc6b5ccad88c2faa0f5466f150178882b74"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/629d5557e635cdbc109a14ed913ba5a540e3f79a"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/6e8eff8ed13b14708bc39f170144eacde494aac6"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/87f21b59ddc618eff9670c174842964ad65fdade"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/8fc56ca49fc0ee1725b55c67bb43ab0dd01f3f52"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/b36dfd6e8cff00cea81c11cc0af88d1564763461"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/dc1a319a4815c074914e2812e0e9cd0164ca682b"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/defa0adeff132cc90ed66915b9a104d9393e1e54"
  } ],
  "database_specific" : {
    "cwe_ids" : [ ],
    "severity" : "HIGH",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-09-11T20:19:40Z"
  }
}