Vulnerability-Lookup

GHSA-28CW-RPQC-WQQJ

Vulnerability from github – Published: 2026-06-14 18:32 – Updated: 2026-06-14 18:32

Details

LiamBindle MQTT-C through version 1.1.6 contains a heap-based out-of-bounds read and integer underflow in the mqtt_unpack_publish_response() function in src/mqtt.c that allows a remote unauthenticated attacker controlling an MQTT broker - or able to inject MQTT traffic into an unencrypted session - to crash a subscribed MQTT-C client and potentially disclose adjacent heap memory by sending a single crafted PUBLISH packet. The function validates only that the fixed-header remaining_length is at least 4, then reads the 16-bit topic_name_size field from the broker-controlled packet and advances the parse pointer by that value without verifying that topic_name_size plus the surrounding overhead fits within remaining_length; it subsequently computes application_message_size as remaining_length - topic_name_size - 2 (QoS 0) or - 4 (QoS greater than 0) in unsigned arithmetic, producing an integer underflow that is then passed to memmove(). A PUBLISH packet with topic_name_size = 0xFFFF and remaining_length = 7 advances the parse pointer 65535 bytes past the receive buffer (out-of-bounds read) and causes an application_message_size near 2^32, crashing the process when the resulting memmove() is executed.

Severity

8.2 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H

7.8 (High)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/AU:Y/V:D

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{
  "affected": [],
  "aliases": [
    "CVE-2026-54412"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-125"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-06-14T18:17:20Z",
    "severity": "HIGH"
  },
  "details": "LiamBindle MQTT-C through version 1.1.6 contains a heap-based out-of-bounds read and integer underflow in the mqtt_unpack_publish_response() function in src/mqtt.c that allows a remote unauthenticated attacker controlling an MQTT broker - or able to inject MQTT traffic into an unencrypted session - to crash a subscribed MQTT-C client and potentially disclose adjacent heap memory by sending a single crafted PUBLISH packet. The function validates only that the fixed-header remaining_length is at least 4, then reads the 16-bit topic_name_size field from the broker-controlled packet and advances the parse pointer by that value without verifying that topic_name_size plus the surrounding overhead fits within remaining_length; it subsequently computes application_message_size as remaining_length - topic_name_size - 2 (QoS 0) or - 4 (QoS greater than 0) in unsigned arithmetic, producing an integer underflow that is then passed to memmove(). A PUBLISH packet with topic_name_size = 0xFFFF and remaining_length = 7 advances the parse pointer 65535 bytes past the receive buffer (out-of-bounds read) and causes an application_message_size near 2^32, crashing the process when the resulting memmove() is executed.",
  "id": "GHSA-28cw-rpqc-wqqj",
  "modified": "2026-06-14T18:32:36Z",
  "published": "2026-06-14T18:32:36Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-54412"
    },
    {
      "type": "WEB",
      "url": "https://cwe.mitre.org/data/definitions/125.html"
    },
    {
      "type": "WEB",
      "url": "https://cwe.mitre.org/data/definitions/191.html"
    },
    {
      "type": "WEB",
      "url": "https://github.com/LiamBindle/MQTT-C"
    },
    {
      "type": "WEB",
      "url": "https://github.com/LiamBindle/MQTT-C/blob/v1.1.6/src/mqtt.c#L1334"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:X/V:D/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-54412 (GCVE-0-2026-54412)

Vulnerability from cvelistv5 – Published: 2026-06-14 17:26 – Updated: 2026-06-15 17:01

Summary

Severity

7.8 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/AU:Y/V:D

8.2 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-125 - Out-of-bounds Read
CWE-191 - Integer Underflow (Wrap or Wraparound)

Assigner

TuranSec

References

4 references

URL	Tags
https://github.com/LiamBindle/MQTT-C	product
https://github.com/LiamBindle/MQTT-C/blob/v1.1.6/…	product
https://cwe.mitre.org/data/definitions/125.html	technical-description
https://cwe.mitre.org/data/definitions/191.html	technical-description

Impacted products

1 product

Vendor	Product	Version
LiamBindle	MQTT-C	Affected: 0 , ≤ 1.1.6 (semver)

Credits

Saidakbarxon Maxsudxonov

Show details on NVD website

JSON

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{
  "containers": {
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      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-54412",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-15T17:01:08.771614Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-15T17:01:16.924Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://github.com/LiamBindle/MQTT-C",
          "defaultStatus": "unknown",
          "product": "MQTT-C",
          "programFiles": [
            "src/mqtt.c"
          ],
          "programRoutines": [
            {
              "name": "mqtt_unpack_publish_response"
            }
          ],
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          "versions": [
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              "lessThanOrEqual": "1.1.6",
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              "version": "0",
              "versionType": "semver"
            }
          ]
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      "credits": [
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          "type": "finder",
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      "impacts": [
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            }
          ]
        }
      ],
      "metrics": [
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            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
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            "attackRequirements": "NONE",
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            "vulnAvailabilityImpact": "HIGH",
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            "vulnIntegrityImpact": "NONE",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
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            }
          ]
        },
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            "confidentialityImpact": "LOW",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
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              "lang": "en",
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      "providerMetadata": {
        "dateUpdated": "2026-06-14T17:27:35.016Z",
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      },
      "references": [
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      ],
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    "assignerShortName": "TuranSec",
    "cveId": "CVE-2026-54412",
    "datePublished": "2026-06-14T17:26:36.740Z",
    "dateReserved": "2026-06-13T16:39:46.122Z",
    "dateUpdated": "2026-06-15T17:01:16.924Z",
    "state": "PUBLISHED"
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  "dataType": "CVE_RECORD",
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}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-28CW-RPQC-WQQJ

CVE-2026-54412 (GCVE-0-2026-54412)

Tags

Sightings

Nomenclature