CVE-2026-80976: Software Security Vulnerability Vulnerability

CRITICAL
Advisory Identifier: GHSA-mh5q-5qhg-xgrv
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CVSS 9.8
Published
Advisory Summary

CVE-2026-80976 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-2026-80976 at a Glance

CVE Identifier CVE-2026-80976
GHSA Identifier GHSA-mh5q-5qhg-xgrv
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-2026-80976

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-2026-80976, 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: seg6: reset IP6CB after IPv6 decapsulation decap_and_validate() pulls the outer SRv6 headers and makes the inner packet the skb network header. The IPv6 control block still contains values collected while parsing the outer packet, including nhoff and extension-header flags. End.DX6 and End.DT6 route the inner IPv6 packet directly to the IPv6 input path. An unprivileged user can reach End.DT6 from a user and net namespace by installing a local SID and injecting an outer packet with Hop-by-Hop and Destination Options headers followed by an SRH and a minimal inner IPv6 packet. The outer extension headers leave a large nhoff in IP6CB. After decapsulation, ip6_protocol_deliver_rcu() uses that stale offset on the inner packet and reads beyond the skb head. KASAN reports: BUG: KASAN: slab-out-of-bounds in ip6_protocol_deliver_rcu ip6_protocol_deliver_rcu+0x1118/0x1450 ip6_input_finish+0x11b/0x240 seg6_local_input_core+0xed/0x2e0 lwtunnel_input+0x1e9/0x4e0 ipv6_rthdr_rcv+0x525f/0x6c50 ip6_protocol_deliver_rcu+0xcb7/0x1450 Before clearing IP6CB for an inner IPv6 packet, save its incoming interface index and L3 slave state. Restore both after the clear and set nhoff to the inner IPv6 base-header nexthdr field. Use IP6CB(skb)->iif rather than skb->skb_iif because VRF processing can replace skb_iif with the L3 master while IP6CB keeps the receiving interface. Preserve IP6SKB_L3SLAVE for the same reason.

References

NVD — CVE-2026-80976 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-80976
git.kernel.org/stable/c/2b154e96fc... WEB
https://git.kernel.org/stable/c/2b154e96fcb3f01fd42765c64e0a56820fbc16eb
git.kernel.org/stable/c/96c74420ac... WEB
https://git.kernel.org/stable/c/96c74420ac92930a7e0f21770818544eee4a93d7
git.kernel.org/stable/c/9ae92198c2... WEB
https://git.kernel.org/stable/c/9ae92198c24d7dacd4070e2f34f6e1ed3a63061c
git.kernel.org/stable/c/a0e2b0a371... WEB
https://git.kernel.org/stable/c/a0e2b0a3718f0cf9fb0ee41710b4a6348a7315c8
git.kernel.org/stable/c/c73fb911e0... WEB
https://git.kernel.org/stable/c/c73fb911e02b9a766c950bc9707f3e3a96ffd702
git.kernel.org/stable/c/cfa186a085... WEB
https://git.kernel.org/stable/c/cfa186a0857a0f831dfca67b16bbc40ecfdf3280
git.kernel.org/stable/c/d1f0d35335... WEB
https://git.kernel.org/stable/c/d1f0d353358987ca87f21d8956e2d2854951130d
git.kernel.org/stable/c/f967455fb2... WEB
https://git.kernel.org/stable/c/f967455fb2a5a2079b9eb5823e9ccf359174bf9f

Frequently Asked Questions

What is CVE-2026-80976?
CVE-2026-80976 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-2026-80976?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2026-80976?
CVE-2026-80976 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-2026-80976?
CVE-2026-80976 is classified under General Security Weakness.
How can I check Maven dependencies for CVE-2026-80976?
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-mh5q-5qhg-xgrv",
  "modified" : "2026-09-14T15:32:21Z",
  "published" : "2026-09-11T21:31:22Z",
  "aliases" : [ "CVE-2026-80976" ],
  "details" : "In the Linux kernel, the following vulnerability has been resolved:\n\nseg6: reset IP6CB after IPv6 decapsulation\n\ndecap_and_validate() pulls the outer SRv6 headers and makes the inner\npacket the skb network header. The IPv6 control block still contains\nvalues collected while parsing the outer packet, including nhoff and\nextension-header flags.\n\nEnd.DX6 and End.DT6 route the inner IPv6 packet directly to the IPv6\ninput path. An unprivileged user can reach End.DT6 from a user and net\nnamespace by installing a local SID and injecting an outer packet with\nHop-by-Hop and Destination Options headers followed by an SRH and a\nminimal inner IPv6 packet.\n\nThe outer extension headers leave a large nhoff in IP6CB. After\ndecapsulation, ip6_protocol_deliver_rcu() uses that stale offset on the\ninner packet and reads beyond the skb head. KASAN reports:\n\n  BUG: KASAN: slab-out-of-bounds in ip6_protocol_deliver_rcu\n  ip6_protocol_deliver_rcu+0x1118/0x1450\n  ip6_input_finish+0x11b/0x240\n  seg6_local_input_core+0xed/0x2e0\n  lwtunnel_input+0x1e9/0x4e0\n  ipv6_rthdr_rcv+0x525f/0x6c50\n  ip6_protocol_deliver_rcu+0xcb7/0x1450\n\nBefore clearing IP6CB for an inner IPv6 packet, save its incoming\ninterface index and L3 slave state. Restore both after the clear and set\nnhoff to the inner IPv6 base-header nexthdr field.\n\nUse IP6CB(skb)->iif rather than skb->skb_iif because VRF processing can\nreplace skb_iif with the L3 master while IP6CB keeps the receiving\ninterface. Preserve IP6SKB_L3SLAVE for the same reason.",
  "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-2026-80976"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/2b154e96fcb3f01fd42765c64e0a56820fbc16eb"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/96c74420ac92930a7e0f21770818544eee4a93d7"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/9ae92198c24d7dacd4070e2f34f6e1ed3a63061c"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/a0e2b0a3718f0cf9fb0ee41710b4a6348a7315c8"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/c73fb911e02b9a766c950bc9707f3e3a96ffd702"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/cfa186a0857a0f831dfca67b16bbc40ecfdf3280"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/d1f0d353358987ca87f21d8956e2d2854951130d"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/f967455fb2a5a2079b9eb5823e9ccf359174bf9f"
  } ],
  "database_specific" : {
    "cwe_ids" : [ ],
    "severity" : "CRITICAL",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-09-11T20:19:03Z"
  }
}