CVE-2026-55428

Status: AnalyzedHigh (8.2)—

Coder allows organizations to provision remote development environments via Terraform. Prior to versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2, the tailnet coordinator validates that an agent's `Addresses` derive from its authenticated UUID but applies no equivalent check to `AllowedIPs`. The coordinator forwards agent-supplied `AllowedIPs` verbatim to tunnel peers which install them into the WireGuard peer configuration. The fix in versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2 validates each `AllowedIPs` prefix against the authenticating agent's UUID just like `Addresses`. As a workaround, monitor coordinator logs for agents advertising unexpected `AllowedIPs` prefixes.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:N
Base score: 8.2

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.40%
Percentile among all scored CVEs: 32
Score date: 10/2/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1210 Exploitation of Remote Serviceslateral movement75 %
Primary impactT1078 Valid Accountsstealth · persistence · privilege escalation · initial access70 %
Secondary impactT1090.003 Multi-hop Proxycommand and control65 %

Vulnerabilidad en validación de AllowedIPs en coordinador de red (CWE-863), permitiendo a agentes autenticados (PR:L) falsificar configuración WireGuard de peers remotos: acceso a redes no autorizadas (T1090.003) y potencial acceso como otros agentes/identidades (T1078) en topología de red de desarr

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Privileged Account Management Application Developer Guidance Active Directory Configuration Vulnerability Scanning User Training User Account Management

Affected technologies (1)

Coder — Coder

CWEs

CWE-285, CWE-863

References

Raw JSON (NVD)

Show

{
  "id": "CVE-2026-55428",
  "cveTags": [],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-55428",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-07-08T13:10:59.507766Z"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "security-advisories@github.com",
        "cvssData": {
          "scope": "CHANGED",
          "version": "3.1",
          "baseScore": 8.2,
          "attackVector": "NETWORK",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:N",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "HIGH",
          "availabilityImpact": "NONE",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.8,
        "exploitabilityScore": 1.8
      }
    ]
  },
  "affected": [
    {
      "source": "security-advisories@github.com",
      "affectedData": [
        {
          "vendor": "coder",
          "product": "coder",
          "versions": [
            {
              "status": "affected",
              "version": ">= 2.34.0, < 2.34.2"
            },
            {
              "status": "affected",
              "version": ">= 2.33.0, < 2.33.8"
            },
            {
              "status": "affected",
              "version": ">= 2.30.0, < 2.32.7"
            },
            {
              "status": "affected",
              "version": "< 2.29.17"
            }
          ]
        }
      ]
    }
  ],
  "published": "2026-07-08T00:16:33.463",
  "references": [
    {
      "url": "https://github.com/coder/coder/pull/26144",
      "tags": [
        "Issue Tracking",
        "Patch"
      ],
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://github.com/coder/coder/releases/tag/v2.29.17",
      "tags": [
        "Release Notes"
      ],
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://github.com/coder/coder/releases/tag/v2.32.7",
      "tags": [
        "Release Notes"
      ],
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://github.com/coder/coder/releases/tag/v2.33.8",
      "tags": [
        "Release Notes"
      ],
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://github.com/coder/coder/releases/tag/v2.34.2",
      "tags": [
        "Release Notes"
      ],
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://github.com/coder/coder/security/advisories/GHSA-wrq8-fcv5-8hvp",
      "tags": [
        "Patch",
        "Vendor Advisory"
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "type": "Secondary",
      "source": "security-advisories@github.com",
      "description": [
        {
          "lang": "en",
          "value": "CWE-285"
        },
        {
          "lang": "en",
          "value": "CWE-863"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "Coder allows organizations to provision remote development environments via Terraform. Prior to versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2, the tailnet coordinator validates that an agent's `Addresses` derive from its authenticated UUID but applies no equivalent check to `AllowedIPs`. The coordinator forwards agent-supplied `AllowedIPs` verbatim to tunnel peers which install them into the WireGuard peer configuration. The fix in versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2 validates each `AllowedIPs` prefix against the authenticating agent's UUID just like `Addresses`. As a workaround, monitor coordinator logs for agents advertising unexpected `AllowedIPs` prefixes."
    }
  ],
  "lastModified": "2026-07-08T19:44:06.553",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:coder:coder:*:*:*:*:*:go:*:*",
              "vulnerable": true,
              "matchCriteriaId": "F97FAF48-192E-4814-82A5-085C44F1D261",
              "versionEndExcluding": "2.29.17"
            },
            {
              "criteria": "cpe:2.3:a:coder:coder:*:*:*:*:*:go:*:*",
              "vulnerable": true,
              "matchCriteriaId": "7ABD4A9B-6AE8-47D8-A1B7-91E42EE0481B",
              "versionEndExcluding": "2.32.7",
              "versionStartIncluding": "2.30.0"
            },
            {
              "criteria": "cpe:2.3:a:coder:coder:*:*:*:*:*:go:*:*",
              "vulnerable": true,
              "matchCriteriaId": "F759EEF3-6EAE-475B-85F8-38E7D7B47438",
              "versionEndExcluding": "2.33.8",
              "versionStartIncluding": "2.33.0"
            },
            {
              "criteria": "cpe:2.3:a:coder:coder:*:*:*:*:*:go:*:*",
              "vulnerable": true,
              "matchCriteriaId": "397A02BF-6CF6-40B1-B792-D7CB9D229050",
              "versionEndExcluding": "2.34.2",
              "versionStartIncluding": "2.34.0"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "security-advisories@github.com"
}