CVE-2025-9820: Software Security Vulnerability Vulnerability

MODERATE
Advisory Identifier: GHSA-337w-h8w7-m899
CVSS 4.0
CWE-121
Published
Advisory Summary

CVE-2025-9820 is a MODERATE (CVSS 4.0) security vulnerability vulnerability (CWE-121: Stack-based Buffer Overflow) affecting Software libraries in the Maven ecosystem. The weakness occurs when a stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).. Remediation is available in the latest vendor maintenance releases.

CVE-2025-9820 at a Glance

CVE Identifier CVE-2025-9820
GHSA Identifier GHSA-337w-h8w7-m899
Severity MODERATE
CVSS v3.1 Base Score 4.0
CWE Classification CWE-121: Stack-based Buffer Overflow
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 4.0

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

Attack Vector Local (AV:L)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality None (C:N)
Integrity None (I:N)
Availability Low (A:L)

How to Fix CVE-2025-9820

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-2025-9820, 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-121: Stack-based Buffer Overflow, where a stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function). 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

A flaw was found in the GnuTLS library, specifically in the gnutls_pkcs11_token_init() function that handles PKCS#11 token initialization. When a token label longer than expected is processed, the function writes past the end of a fixed-size stack buffer. This programming error can cause the application using GnuTLS to crash or, in certain conditions, be exploited for code execution. As a result, systems or applications relying on GnuTLS may be vulnerable to a denial of service or local privilege escalation attacks.

References

NVD — CVE-2025-9820 NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-9820
Software Security Information SECURITY
https://www.gnutls.org/security-new.html#GNUTLS-SA-2025-11-18
gitlab.com/gnutls/gnutls/-/iss... WEB
https://gitlab.com/gnutls/gnutls/-/issues/1732
gitlab.com/gnutls/gnutls/-/com... WEB
https://gitlab.com/gnutls/gnutls/-/commit/1d56f96f6ab5034d677136b9d50b5a75dff0faf5
cert-portal.siemens.com/productcert/html/ss... WEB
https://cert-portal.siemens.com/productcert/html/ssa-032379.html
bugzilla.redhat.com/show_bug.cgi WEB
https://bugzilla.redhat.com/show_bug.cgi?id=2392528
Software Security Information SECURITY
https://access.redhat.com/security/cve/CVE-2025-9820
access.redhat.com/errata/rhsa-2026:82... WEB
https://access.redhat.com/errata/RHSA-2026:82857
access.redhat.com/errata/rhsa-2026:82... WEB
https://access.redhat.com/errata/RHSA-2026:82372
access.redhat.com/errata/rhsa-2026:82... WEB
https://access.redhat.com/errata/RHSA-2026:82354
access.redhat.com/errata/rhsa-2026:82... WEB
https://access.redhat.com/errata/RHSA-2026:82347
access.redhat.com/errata/rhsa-2026:74... WEB
https://access.redhat.com/errata/RHSA-2026:7477
access.redhat.com/errata/rhsa-2026:73... WEB
https://access.redhat.com/errata/RHSA-2026:7329
access.redhat.com/errata/rhsa-2026:56... WEB
https://access.redhat.com/errata/RHSA-2026:5606
access.redhat.com/errata/rhsa-2026:55... WEB
https://access.redhat.com/errata/RHSA-2026:5585
access.redhat.com/errata/rhsa-2026:49... WEB
https://access.redhat.com/errata/RHSA-2026:4943
access.redhat.com/errata/rhsa-2026:46... WEB
https://access.redhat.com/errata/RHSA-2026:4655
access.redhat.com/errata/rhsa-2026:41... WEB
https://access.redhat.com/errata/RHSA-2026:4188
access.redhat.com/errata/rhsa-2026:34... WEB
https://access.redhat.com/errata/RHSA-2026:3477
access.redhat.com/errata/rhsa-2026:13... WEB
https://access.redhat.com/errata/RHSA-2026:13812
Software Security Information SECURITY
http://www.openwall.com/lists/oss-security/2025/11/20/2

Frequently Asked Questions

What is CVE-2025-9820?
CVE-2025-9820 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-121: Stack-based Buffer Overflow.
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2025-9820?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2025-9820?
CVE-2025-9820 has a CVSS v3.1 base score of 4.0 (MODERATE) with vector string CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.
What CWE is associated with CVE-2025-9820?
CVE-2025-9820 is classified under CWE-121: Stack-based Buffer Overflow (A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).).
How can I check Maven dependencies for CVE-2025-9820?
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
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