CVE-2026-68124: Software Security Vulnerability Vulnerability

CRITICAL
Advisory Identifier: GHSA-c8wc-v527-8f9g
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CVSS 9.6
Published
Advisory Summary

CVE-2026-68124 is a CRITICAL (CVSS 9.6) security vulnerability vulnerability (General Security Weakness) affecting Software libraries in the Maven ecosystem. Remediation is available in the latest vendor maintenance releases.

CVE-2026-68124 at a Glance

CVE Identifier CVE-2026-68124
GHSA Identifier GHSA-c8wc-v527-8f9g
Severity CRITICAL
CVSS v3.1 Base Score 9.6
CWE Classification General Security Weakness
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 9.6

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

Attack Vector Adjacent (AV:A)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Changed (S:C)
Confidentiality High (C:H)
Integrity High (I:H)
Availability High (A:H)

How to Fix CVE-2026-68124

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-2026-68124, 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: mctp: serial: handle zero-length frames to prevent rx buffer overflow The MCTP serial receive state machine reads a frame length byte in mctp_serial_push_header() case 2 and validates it upper-bound-only: if (c > MCTP_SERIAL_FRAME_MTU) { dev->rxstate = STATE_ERR; } else { dev->rxlen = c; dev->rxpos = 0; dev->rxstate = STATE_DATA; ... } A length of zero passes this check, so rxlen is set to 0 and the state machine advances to STATE_DATA. In mctp_serial_push() STATE_DATA, the incoming byte is stored and rxpos incremented before the terminator is dev->rxbuf[dev->rxpos] = c; dev->rxpos++; dev->rxstate = STATE_DATA; if (dev->rxpos == dev->rxlen) { dev->rxpos = 0; dev->rxstate = STATE_TRAILER; } With rxlen == 0 the "rxpos == rxlen" terminator can never fire (rxpos is already 1 on the first data byte), so subsequent bytes are written past the end of the fixed 74-byte rxbuf, which is the last member of the netdev private area. Every following data byte is an attacker-controlled 1-byte out-of-bounds heap write, and the overflow continues until a frame (0x7e) or escape byte resets the parser -- effectively unbounded. Reaching this requires CAP_NET_ADMIN to attach the N_MCTP line discipline and bring the resulting mctpserialN netdev up, after which the bytes arrive via the tty receive path. Route a zero-length frame straight to STATE_TRAILER instead of STATE_DATA. The trailer/framing bytes are still consumed, and the frame resolves to a zero-length skb that the MCTP core rejects; the parser never enters STATE_DATA with rxlen == 0, so the out-of-bounds write can no longer occur. KASAN, on a frame of 0x7e 0x01 0x00 followed by data bytes (before this change): UBSAN: array-index-out-of-bounds in drivers/net/mctp/mctp-serial.c:370 index 74 is out of range for type 'u8 [74]' BUG: KASAN: slab-out-of-bounds in mctp_serial_tty_receive_buf Write of size 1 at addr ... by task kworker/u16:0 mctp_serial_tty_receive_buf tty_ldisc_receive_buf flush_to_ldisc Allocated by task 152: alloc_netdev_mqs mctp_serial_open v2: route zero-length frames to STATE_TRAILER instead of STATE_ERR so the trailer/framing bytes are still consumed (Jeremy Kerr). Found by 0sec automated security-research tooling (https://0sec.ai).

References

NVD — CVE-2026-68124 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-68124
git.kernel.org/stable/c/06a6b60612... WEB
https://git.kernel.org/stable/c/06a6b606129c8a25cd457760f5370f3ff01fe05d
git.kernel.org/stable/c/36dc6d6964... WEB
https://git.kernel.org/stable/c/36dc6d6964a3b90411cc7944cd9b8b6f67b9807b
git.kernel.org/stable/c/64b96ae791... WEB
https://git.kernel.org/stable/c/64b96ae7912244d55257aa330d9569ee0a8f8d99
git.kernel.org/stable/c/68819427bc... WEB
https://git.kernel.org/stable/c/68819427bc07eca7963a9e8be19e5272cc29186c
git.kernel.org/stable/c/793b9b729f... WEB
https://git.kernel.org/stable/c/793b9b729f1e8de57be8c8daf1a9838be96cabed
git.kernel.org/stable/c/f80ba170d7... WEB
https://git.kernel.org/stable/c/f80ba170d7b3a44e3d244a2c8e06031d61bf3b23

Frequently Asked Questions

What is CVE-2026-68124?
CVE-2026-68124 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-2026-68124?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2026-68124?
CVE-2026-68124 has a CVSS v3.1 base score of 9.6 (CRITICAL) with vector string CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H.
What CWE is associated with CVE-2026-68124?
CVE-2026-68124 is classified under General Security Weakness.
How can I check Maven dependencies for CVE-2026-68124?
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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  "schema_version" : "1.4.0",
  "id" : "GHSA-c8wc-v527-8f9g",
  "modified" : "2026-08-19T18:32:05Z",
  "published" : "2026-08-10T15:33:36Z",
  "aliases" : [ "CVE-2026-68124" ],
  "details" : "In the Linux kernel, the following vulnerability has been resolved:\n\nmctp: serial: handle zero-length frames to prevent rx buffer overflow\n\nThe MCTP serial receive state machine reads a frame length byte in\nmctp_serial_push_header() case 2 and validates it upper-bound-only:\n\n\tif (c > MCTP_SERIAL_FRAME_MTU) {\n\t\tdev->rxstate = STATE_ERR;\n\t} else {\n\t\tdev->rxlen = c;\n\t\tdev->rxpos = 0;\n\t\tdev->rxstate = STATE_DATA;\n\t\t...\n\t}\n\nA length of zero passes this check, so rxlen is set to 0 and the state\nmachine advances to STATE_DATA. In mctp_serial_push() STATE_DATA, the\nincoming byte is stored and rxpos incremented before the terminator is\n\n\tdev->rxbuf[dev->rxpos] = c;\n\tdev->rxpos++;\n\tdev->rxstate = STATE_DATA;\n\tif (dev->rxpos == dev->rxlen) {\n\t\tdev->rxpos = 0;\n\t\tdev->rxstate = STATE_TRAILER;\n\t}\n\nWith rxlen == 0 the \"rxpos == rxlen\" terminator can never fire (rxpos is\nalready 1 on the first data byte), so subsequent bytes are written past\nthe end of the fixed 74-byte rxbuf, which is the last member of the\nnetdev private area. Every following data byte is an attacker-controlled\n1-byte out-of-bounds heap write, and the overflow continues until a\nframe (0x7e) or escape byte resets the parser -- effectively unbounded.\n\nReaching this requires CAP_NET_ADMIN to attach the N_MCTP line\ndiscipline and bring the resulting mctpserialN netdev up, after which\nthe bytes arrive via the tty receive path.\n\nRoute a zero-length frame straight to STATE_TRAILER instead of\nSTATE_DATA. The trailer/framing bytes are still consumed, and the frame\nresolves to a zero-length skb that the MCTP core rejects; the parser\nnever enters STATE_DATA with rxlen == 0, so the out-of-bounds write can\nno longer occur.\n\nKASAN, on a frame of 0x7e 0x01 0x00 followed by data bytes (before this\nchange):\n\n  UBSAN: array-index-out-of-bounds in drivers/net/mctp/mctp-serial.c:370\n  index 74 is out of range for type 'u8 [74]'\n  BUG: KASAN: slab-out-of-bounds in mctp_serial_tty_receive_buf\n  Write of size 1 at addr ... by task kworker/u16:0\n   mctp_serial_tty_receive_buf\n   tty_ldisc_receive_buf\n   flush_to_ldisc\n  Allocated by task 152:\n   alloc_netdev_mqs\n   mctp_serial_open\n\nv2: route zero-length frames to STATE_TRAILER instead of STATE_ERR so\n    the trailer/framing bytes are still consumed (Jeremy Kerr).\n\nFound by 0sec automated security-research tooling (https://0sec.ai).",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H"
  } ],
  "affected" : [ ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-68124"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/06a6b606129c8a25cd457760f5370f3ff01fe05d"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/36dc6d6964a3b90411cc7944cd9b8b6f67b9807b"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/64b96ae7912244d55257aa330d9569ee0a8f8d99"
  }, {
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    "url" : "https://git.kernel.org/stable/c/68819427bc07eca7963a9e8be19e5272cc29186c"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/793b9b729f1e8de57be8c8daf1a9838be96cabed"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/f80ba170d7b3a44e3d244a2c8e06031d61bf3b23"
  } ],
  "database_specific" : {
    "cwe_ids" : [ ],
    "severity" : "CRITICAL",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-08-10T13:19:57Z"
  }
}