CVE-2026-89537: Software Security Vulnerability Vulnerability

CRITICAL
Advisory Identifier: GHSA-8jwh-2pr5-8fq7
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CVSS 9.1
Published
Advisory Summary

CVE-2026-89537 is a CRITICAL (CVSS 9.1) security vulnerability vulnerability (General Security Weakness) affecting Software libraries in the Maven ecosystem. Remediation is available in the latest vendor maintenance releases.

CVE-2026-89537 at a Glance

CVE Identifier CVE-2026-89537
GHSA Identifier GHSA-8jwh-2pr5-8fq7
Severity CRITICAL
CVSS v3.1 Base Score 9.1
CWE Classification General Security Weakness
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 9.1

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

How to Fix CVE-2026-89537

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-2026-89537, 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: SUNRPC: Reject short RFC 4121 MIC tokens in gss_krb5_verify_mic_v2 gss_krb5_verify_mic_v2() reads the token ID at ptr[0..1], the flags byte at ptr[2], and padding at ptr[3..7], then passes ptr + GSS_KRB5_TOK_HDR_LEN and cksum_len to gss_krb5_mic_build_sg(). None of these accesses check read_token->len first. The minimum safe token size is GSS_KRB5_TOK_HDR_LEN (16) plus ctx->krb5e->cksum_len (12-24, depending on the enctype). All callers accept shorter tokens from the wire: - gss_unwrap_resp_integ() enforces only an upper bound (offset + len <= rcv_buf->len) before allocating mic.data = kmalloc(len) and passing it to gss_verify_mic(). A malicious NFS server can therefore supply a short checksum opaque, producing a small slab allocation that the Kerberos MIC verifier reads past. - gss_validate() enforces only len <= RPC_MAX_AUTH_SIZE (400) before passing the wire-supplied length to gss_validate_seqno_mic(), which constructs a mic xdr_netobj and calls gss_verify_mic(). - svcauth_gss_verify_header() enforces only checksum.len >= XDR_UNIT (4 bytes) before dispatching to gss_verify_mic(). - svcauth_gss_unwrap_integ() checks only that the checksum fits in gsd->gsd_scratch. Add a length guard at the top of gss_krb5_verify_mic_v2(), before any ptr[] access or scatterlist construction. Well-formed MIC tokens from gss_krb5_get_mic_v2() already have exactly GSS_KRB5_TOK_HDR_LEN + cksum_len bytes, so valid traffic is unaffected.

References

NVD — CVE-2026-89537 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-89537
git.kernel.org/stable/c/7a946b2e72... WEB
https://git.kernel.org/stable/c/7a946b2e7207f968902f2147ab9b30726f82f7ab
git.kernel.org/stable/c/996dd15f60... WEB
https://git.kernel.org/stable/c/996dd15f60121bdd7896b4554458f8806d608063
git.kernel.org/stable/c/b94f6719dc... WEB
https://git.kernel.org/stable/c/b94f6719dcd9f7a609bc5f459f85795900e77d25

Frequently Asked Questions

What is CVE-2026-89537?
CVE-2026-89537 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-2026-89537?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2026-89537?
CVE-2026-89537 has a CVSS v3.1 base score of 9.1 (CRITICAL) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H.
What CWE is associated with CVE-2026-89537?
CVE-2026-89537 is classified under General Security Weakness.
How can I check Maven dependencies for CVE-2026-89537?
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-8jwh-2pr5-8fq7",
  "modified" : "2026-10-15T12:30:45Z",
  "published" : "2026-09-11T21:31:31Z",
  "aliases" : [ "CVE-2026-89537" ],
  "details" : "In the Linux kernel, the following vulnerability has been resolved:\n\nSUNRPC: Reject short RFC 4121 MIC tokens in gss_krb5_verify_mic_v2\n\ngss_krb5_verify_mic_v2() reads the token ID at ptr[0..1], the flags\nbyte at ptr[2], and padding at ptr[3..7], then passes\nptr + GSS_KRB5_TOK_HDR_LEN and cksum_len to gss_krb5_mic_build_sg().\nNone of these accesses check read_token->len first.\n\nThe minimum safe token size is GSS_KRB5_TOK_HDR_LEN (16) plus\nctx->krb5e->cksum_len (12-24, depending on the enctype).  All callers\naccept shorter tokens from the wire:\n\n - gss_unwrap_resp_integ() enforces only an upper bound\n   (offset + len <= rcv_buf->len) before allocating\n   mic.data = kmalloc(len) and passing it to gss_verify_mic().\n   A malicious NFS server can therefore supply a short checksum\n   opaque, producing a small slab allocation that the Kerberos MIC\n   verifier reads past.\n\n - gss_validate() enforces only len <= RPC_MAX_AUTH_SIZE (400)\n   before passing the wire-supplied length to\n   gss_validate_seqno_mic(), which constructs a mic xdr_netobj\n   and calls gss_verify_mic().\n\n - svcauth_gss_verify_header() enforces only\n   checksum.len >= XDR_UNIT (4 bytes) before dispatching to\n   gss_verify_mic().\n\n - svcauth_gss_unwrap_integ() checks only that the checksum fits\n   in gsd->gsd_scratch.\n\nAdd a length guard at the top of gss_krb5_verify_mic_v2(), before any\nptr[] access or scatterlist construction.  Well-formed MIC tokens from\ngss_krb5_get_mic_v2() already have exactly GSS_KRB5_TOK_HDR_LEN +\ncksum_len bytes, so valid traffic is unaffected.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H"
  } ],
  "affected" : [ ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-89537"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/7a946b2e7207f968902f2147ab9b30726f82f7ab"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/996dd15f60121bdd7896b4554458f8806d608063"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/b94f6719dcd9f7a609bc5f459f85795900e77d25"
  } ],
  "database_specific" : {
    "cwe_ids" : [ ],
    "severity" : "CRITICAL",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-09-11T20:19:36Z"
  }
}