CVE-2026-43037: Software Security Vulnerability Vulnerability

CRITICAL
Advisory Identifier: GHSA-p2wf-qj6m-x5fg
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CVSS 9.8
CWE-121 CWE-843 CWE-787
Published
Advisory Summary

CVE-2026-43037 is a CRITICAL (CVSS 9.8) 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-2026-43037 at a Glance

CVE Identifier CVE-2026-43037
GHSA Identifier GHSA-p2wf-qj6m-x5fg
Severity CRITICAL
CVSS v3.1 Base Score 9.8
CWE Classification CWE-121: Stack-based Buffer Overflow
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-2026-43037

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-2026-43037, 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

In the Linux kernel, the following vulnerability has been resolved: ip6_tunnel: clear skb2->cb[] in ip4ip6_err() Oskar Kjos reported the following problem. ip4ip6_err() calls icmp_send() on a cloned skb whose cb[] was written by the IPv6 receive path as struct inet6_skb_parm. icmp_send() passes IPCB(skb2) to __ip_options_echo(), which interprets that cb[] region as struct inet_skb_parm (IPv4). The layouts differ: inet6_skb_parm.nhoff at offset 14 overlaps inet_skb_parm.opt.rr, producing a non-zero rr value. __ip_options_echo() then reads optlen from attacker-controlled packet data at sptr[rr+1] and copies that many bytes into dopt->__data, a fixed 40-byte stack buffer (IP_OPTIONS_DATA_FIXED_SIZE). To fix this we clear skb2->cb[], as suggested by Oskar Kjos. Also add minimal IPv4 header validation (version == 4, ihl >= 5).

References

NVD — CVE-2026-43037 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-43037
access.redhat.com/errata/rhsa-2026:22... WEB
https://access.redhat.com/errata/RHSA-2026:22900
access.redhat.com/errata/rhsa-2026:28... WEB
https://access.redhat.com/errata/RHSA-2026:28741
access.redhat.com/errata/rhsa-2026:28... WEB
https://access.redhat.com/errata/RHSA-2026:28742
access.redhat.com/errata/rhsa-2026:28... WEB
https://access.redhat.com/errata/RHSA-2026:28748
access.redhat.com/errata/rhsa-2026:28... WEB
https://access.redhat.com/errata/RHSA-2026:28749
access.redhat.com/errata/rhsa-2026:28... WEB
https://access.redhat.com/errata/RHSA-2026:28750
access.redhat.com/errata/rhsa-2026:28... WEB
https://access.redhat.com/errata/RHSA-2026:28887
access.redhat.com/errata/rhsa-2026:28... WEB
https://access.redhat.com/errata/RHSA-2026:28962
access.redhat.com/errata/rhsa-2026:33... WEB
https://access.redhat.com/errata/RHSA-2026:33486
access.redhat.com/errata/rhsa-2026:34... WEB
https://access.redhat.com/errata/RHSA-2026:34098
access.redhat.com/errata/rhsa-2026:41... WEB
https://access.redhat.com/errata/RHSA-2026:41236
access.redhat.com/errata/rhsa-2026:44... WEB
https://access.redhat.com/errata/RHSA-2026:44232
Software Security Information SECURITY
https://access.redhat.com/security/cve/CVE-2026-43037
bugzilla.redhat.com/show_bug.cgi WEB
https://bugzilla.redhat.com/show_bug.cgi?id=2464351
git.kernel.org/stable/c/1063515ce1... WEB
https://git.kernel.org/stable/c/1063515ce15ff31065c4e7f8265f4c2fd3c54876
git.kernel.org/stable/c/2cc6e3b0fe... WEB
https://git.kernel.org/stable/c/2cc6e3b0fe0f0242d1f530a93a4924f48ab85ba5
git.kernel.org/stable/c/2edfa31769... WEB
https://git.kernel.org/stable/c/2edfa31769a4add828a7e604b21cb82aaaa05925
git.kernel.org/stable/c/4a622658f3... WEB
https://git.kernel.org/stable/c/4a622658f384b03560834cbe8ffcfe69a278f7c8
git.kernel.org/stable/c/590f622669... WEB
https://git.kernel.org/stable/c/590f622669b97eaf7b57a1de7b0a6e68c5d8b2c3
git.kernel.org/stable/c/a0c4ce9900... WEB
https://git.kernel.org/stable/c/a0c4ce9900a108eaf55d0f3b399cb55999647d39
git.kernel.org/stable/c/d6621f6019... WEB
https://git.kernel.org/stable/c/d6621f60192fe10c047a4487be42a6f4c150707f
git.kernel.org/stable/c/ea9f65b27c... WEB
https://git.kernel.org/stable/c/ea9f65b27c8404e164848ebff1443310fd187629
Software Security Information SECURITY
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43037.json
access.redhat.com/errata/rhsa-2026:22... WEB
https://access.redhat.com/errata/RHSA-2026:22940
access.redhat.com/errata/rhsa-2026:22... WEB
https://access.redhat.com/errata/RHSA-2026:22964
access.redhat.com/errata/rhsa-2026:23... WEB
https://access.redhat.com/errata/RHSA-2026:23224
access.redhat.com/errata/rhsa-2026:23... WEB
https://access.redhat.com/errata/RHSA-2026:23237
access.redhat.com/errata/rhsa-2026:24... WEB
https://access.redhat.com/errata/RHSA-2026:24343
access.redhat.com/errata/rhsa-2026:25... WEB
https://access.redhat.com/errata/RHSA-2026:25044
access.redhat.com/errata/rhsa-2026:25... WEB
https://access.redhat.com/errata/RHSA-2026:25120
access.redhat.com/errata/rhsa-2026:25... WEB
https://access.redhat.com/errata/RHSA-2026:25121
access.redhat.com/errata/rhsa-2026:25... WEB
https://access.redhat.com/errata/RHSA-2026:25181
access.redhat.com/errata/rhsa-2026:25... WEB
https://access.redhat.com/errata/RHSA-2026:25186
access.redhat.com/errata/rhsa-2026:25... WEB
https://access.redhat.com/errata/RHSA-2026:25191
access.redhat.com/errata/rhsa-2026:25... WEB
https://access.redhat.com/errata/RHSA-2026:25193
access.redhat.com/errata/rhsa-2026:25... WEB
https://access.redhat.com/errata/RHSA-2026:25200
access.redhat.com/errata/rhsa-2026:25... WEB
https://access.redhat.com/errata/RHSA-2026:25217
access.redhat.com/errata/rhsa-2026:25... WEB
https://access.redhat.com/errata/RHSA-2026:25533
access.redhat.com/errata/rhsa-2026:25... WEB
https://access.redhat.com/errata/RHSA-2026:25534
access.redhat.com/errata/rhsa-2026:26... WEB
https://access.redhat.com/errata/RHSA-2026:26528
access.redhat.com/errata/rhsa-2026:26... WEB
https://access.redhat.com/errata/RHSA-2026:26535
access.redhat.com/errata/rhsa-2026:26... WEB
https://access.redhat.com/errata/RHSA-2026:26542
access.redhat.com/errata/rhsa-2026:27... WEB
https://access.redhat.com/errata/RHSA-2026:27719
access.redhat.com/errata/rhsa-2026:27... WEB
https://access.redhat.com/errata/RHSA-2026:27729
access.redhat.com/errata/rhsa-2026:28... WEB
https://access.redhat.com/errata/RHSA-2026:28738
access.redhat.com/errata/rhsa-2026:28... WEB
https://access.redhat.com/errata/RHSA-2026:28740

Frequently Asked Questions

What is CVE-2026-43037?
CVE-2026-43037 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-2026-43037?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2026-43037?
CVE-2026-43037 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-2026-43037?
CVE-2026-43037 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-2026-43037?
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 
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