CVE-2026-84782: Software Security Vulnerability Vulnerability

HIGH
Advisory Identifier: GHSA-6w84-hw79-7wgf
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CVSS 8.2
CWE-125
Published
Advisory Summary

CVE-2026-84782 is a HIGH (CVSS 8.2) security vulnerability vulnerability (CWE-125: Out-of-bounds Read) affecting Software libraries in the Maven ecosystem. The weakness occurs when the product reads data past the end, or before the beginning, of the intended buffer.. Remediation is available in the latest vendor maintenance releases.

CVE-2026-84782 at a Glance

CVE Identifier CVE-2026-84782
GHSA Identifier GHSA-6w84-hw79-7wgf
Severity HIGH
CVSS v3.1 Base Score 8.2
CWE Classification CWE-125: Out-of-bounds Read
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 8.2

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:L/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 Low (C:L)
Integrity None (I:N)
Availability High (A:H)

How to Fix CVE-2026-84782

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-2026-84782, 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-125: Out-of-bounds Read, where the product reads data past the end, or before the beginning, of the intended buffer. 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

Issue summary: The DTLS retransmission logic does not correctly handle a handshake message write that is suspended part-way through. The retransmitted message can be read past the message buffer and the retransmission overwrites the internal state the suspended write needs to resume correctly. Impact summary: The retransmitted message can disclose a heap memory to the peer as plaintext handshake data or cause a crash and a Denial of Service when the read reaches an unmapped memory region. CWE: CWE-125: Out-of-bounds Read Description: DTLS handshake messages can be written out in multiple fragments, and a write can suspend mid-message (returning WANT_WRITE) if the underlying transport temporarily cannot accept more data. While such a write is suspended, the DTLS retransmission timer may independently fire and ask the retransmission logic to resend an earlier, already-acknowledged-as-sent message from its retransmit queue. The retransmission logic reused the same internal buffer and position tracking as the message that was still being written, without resetting the position back to the start of the message being retransmitted. As a result the retransmission was read starting from wherever the suspended write had left off, producing a mislabelled message whose body was leftover bytes from the other, larger message still in flight - content that was never meant to be sent at that point, and which could run past the end of the allocated buffer. Separately, even when the retransmission is positioned correctly, allowing it to run to completion while another write is suspended overwrites the same shared bookkeeping that the suspended write depends on to resume. When the application later resumes the suspended write (via a subsequent SSL_read(), SSL_write(), SSL_accept(), or SSL_connect() call), it finds that bookkeeping in a state inconsistent with the message and aborts the process in a debugging build. The fix resets the retransmission's read position to the start of the message before resending, and skips retransmission entirely whenever a handshake write is still suspended, deferring to the next call that resumes it instead. FIPS impact: no The affected code is outside the FIPS module boundary.

References

NVD — CVE-2026-84782 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-84782
Security Fix Commit FIX COMMIT
https://github.com/openssl/openssl/commit/906cf0ef1c85ca40ce69163e9086d6d3fe292943
Security Fix Commit FIX COMMIT
https://github.com/openssl/openssl/commit/9f6b34422af7eb5dac61322e33dac1ae989fa628
Security Fix Commit FIX COMMIT
https://github.com/openssl/openssl/commit/a383dafdd754eb5b22bf45e37e1bff9d07277a58
Security Fix Commit FIX COMMIT
https://github.com/openssl/openssl/commit/d951e02ede8f6a6ff8150546db44b34f0518192c
openssl-library.org/news/secadv/2026092... WEB
https://openssl-library.org/news/secadv/20260929.txt

Frequently Asked Questions

What is CVE-2026-84782?
CVE-2026-84782 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-125: Out-of-bounds Read.
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2026-84782?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2026-84782?
CVE-2026-84782 has a CVSS v3.1 base score of 8.2 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H.
What CWE is associated with CVE-2026-84782?
CVE-2026-84782 is classified under CWE-125: Out-of-bounds Read (The product reads data past the end, or before the beginning, of the intended buffer.).
How can I check Maven dependencies for CVE-2026-84782?
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-6w84-hw79-7wgf",
  "modified" : "2026-09-29T18:31:45Z",
  "published" : "2026-09-29T18:31:45Z",
  "aliases" : [ "CVE-2026-84782" ],
  "details" : "Issue summary: The DTLS retransmission logic does not correctly handle\na handshake message write that is suspended part-way through.\nThe retransmitted message can be read past the message buffer and\nthe retransmission overwrites the internal state the suspended write\nneeds to resume correctly.\n\nImpact summary: The retransmitted message can disclose a heap memory\nto the peer as plaintext handshake data or cause a crash and a Denial\nof Service when the read reaches an unmapped memory region.\n\nCWE: CWE-125: Out-of-bounds Read\n\nDescription: DTLS handshake messages can be written out in multiple\nfragments, and a write can suspend mid-message (returning WANT_WRITE)\nif the underlying transport temporarily cannot accept more data. While\nsuch a write is suspended, the DTLS retransmission timer may\nindependently fire and ask the retransmission logic to resend an\nearlier, already-acknowledged-as-sent message from its retransmit\nqueue.\n\nThe retransmission logic reused the same internal buffer and position\ntracking as the message that was still being written, without\nresetting the position back to the start of the message being\nretransmitted. As a result the retransmission was read starting from\nwherever the suspended write had left off, producing a mislabelled\nmessage whose body was leftover bytes from the other, larger message\nstill in flight - content that was never meant to be sent at that\npoint, and which could run past the end of the allocated buffer.\n\nSeparately, even when the retransmission is positioned correctly,\nallowing it to run to completion while another write is suspended\noverwrites the same shared bookkeeping that the suspended write\ndepends on to resume. When the application later resumes the\nsuspended write (via a subsequent SSL_read(), SSL_write(),\nSSL_accept(), or SSL_connect() call), it finds that bookkeeping in a\nstate inconsistent with the message and aborts the process in\na debugging build.\n\nThe fix resets the retransmission's read position to the start of the\nmessage before resending, and skips retransmission entirely whenever a\nhandshake write is still suspended, deferring to the next call that\nresumes it instead.\n\nFIPS impact: no\nThe affected code is outside the FIPS module boundary.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H"
  } ],
  "affected" : [ ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-84782"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/openssl/openssl/commit/906cf0ef1c85ca40ce69163e9086d6d3fe292943"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/openssl/openssl/commit/9f6b34422af7eb5dac61322e33dac1ae989fa628"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/openssl/openssl/commit/a383dafdd754eb5b22bf45e37e1bff9d07277a58"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/openssl/openssl/commit/d951e02ede8f6a6ff8150546db44b34f0518192c"
  }, {
    "type" : "WEB",
    "url" : "https://openssl-library.org/news/secadv/20260929.txt"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-125" ],
    "severity" : "HIGH",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-09-29T16:17:12Z"
  }
}