Vulnerability-Lookup

GHSA-VHMP-9F3G-3F36

Vulnerability from github – Published: 2026-06-23 18:31 – Updated: 2026-06-25 18:30

Details

dhcpcd through 10.3.2, fixed in commit 2f00c7b, contains a one-byte stack out-of-bounds write vulnerability in dhcp6_makemessage() in src/dhcp6.c that allows unauthenticated same-link attackers to write beyond a fixed local buffer by serializing an oversized RFC6603 OPTION_PD_EXCLUDE option body. Attackers can send a crafted DHCPv6 ADVERTISE message containing an IA_PD IAPREFIX /0 with a valid OPTION_PD_EXCLUDE using an exclude prefix length of /121 through /128 to trigger the out-of-bounds write and potentially corrupt adjacent stack memory.

Severity

5.3 (Medium)


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

6.0 (Medium)


                  
                    CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

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JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-56115"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-787",
      "CWE-862"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-06-23T17:17:09Z",
    "severity": "MODERATE"
  },
  "details": "dhcpcd through 10.3.2, fixed in commit 2f00c7b, contains a one-byte stack out-of-bounds write vulnerability in dhcp6_makemessage() in src/dhcp6.c that allows unauthenticated same-link attackers to write beyond a fixed local buffer by serializing an oversized RFC6603 OPTION_PD_EXCLUDE option body. Attackers can send a crafted DHCPv6 ADVERTISE message containing an IA_PD IAPREFIX /0 with a valid OPTION_PD_EXCLUDE using an exclude prefix length of /121 through /128 to trigger the out-of-bounds write and potentially corrupt adjacent stack memory.",
  "id": "GHSA-vhmp-9f3g-3f36",
  "modified": "2026-06-25T18:30:34Z",
  "published": "2026-06-23T18:31:43Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-56115"
    },
    {
      "type": "WEB",
      "url": "https://github.com/garybowers/bootimus/issues/84"
    },
    {
      "type": "WEB",
      "url": "https://github.com/NetworkConfiguration/dhcpcd/commit/2f00c7bfc408b6582d331932dfa47829c4819029"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/bootimus-broken-access-control-via-jwtmiddleware-authorization-bypass"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/dhcpcd-stack-out-of-bounds-write-in-dhcp6-makemessage"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/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:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-56115 (GCVE-0-2026-56115)

Vulnerability from cvelistv5 – Published: 2026-06-23 16:08 – Updated: 2026-07-28 01:49 X_Open Source

Title

Bootimus 0.1.70 Broken Access Control via JWTMiddleware Authorization Bypass

Summary

Bootimus through 0.1.70 contains a broken access control vulnerability that allows authenticated low-privileged users to perform administrative actions by exploiting missing role enforcement in the JWTMiddleware function in internal/auth/auth.go, which validates JWT tokens and account status but fails to inspect the is_admin flag. Attackers can send requests to any endpoint under the /api/users path to create new administrator accounts or reset administrator passwords, thereby gaining full control of the server and the ability to modify boot menus and installation scripts served to PXE clients.

Severity

8.7 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

8.8 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-23 17:07 UTC

CWE

CWE-862 - Missing Authorization

Assigner

VulnCheck mitre root

References

2 references

URL	Tags
https://github.com/garybowers/bootimus/issues/84	technical-descriptionexploit
https://www.vulncheck.com/advisories/bootimus-bro…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
garybowers	bootimus	Affected: 0 , ≤ 0.1.70 (semver) cpe:2.3:a:bootimus:bootimus::::::::

Date Public

2026-06-25 00:00

Credits

djnn

Show details on NVD website

JSON

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  "containers": {
    "adp": [
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        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-56115",
                "options": [
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                    "Exploitation": "none"
                  },
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                  },
                  {
                    "Technical Impact": "partial"
                  }
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                "role": "CISA Coordinator",
                "timestamp": "2026-06-23T17:07:56.273135Z",
                "version": "2.0.3"
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    "cna": {
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              "status": "affected",
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      ],
      "metrics": [
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          "cvssV4_0": {
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            "exploitMaturity": "NOT_DEFINED",
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            "vulnerabilityResponseEffort": "NOT_DEFINED"
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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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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GHSA-VHMP-9F3G-3F36

CVE-2026-56115 (GCVE-0-2026-56115)

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