CVE-2026-48780

Status: DeferredHigh (8.2)—

Forem is open source software for building communities. Prior to commit a2ab6d4, a maliciously crafted email address could allow an attacker to bypass domain allowlist or denylist restrictions and gain access to invite-only forem deployments. The issue is patched as of `a2ab6d4`. As a workaround, some SMTP servers and email delivery providers may drop or refuse to send maliciously crafted email addresses.

CVSS

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

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.37%
Percentile among all scored CVEs: 29
Score date: 10/5/2026

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.

ExploitationT1190 Exploit Public-Facing Applicationinitial access85 %
Primary impactT1078 Valid Accountsstealth · persistence · privilege escalation · initial access80 %
Secondary impactT1565.002 Transmitted Data Manipulationimpact70 %

Vector de red sin autenticación (AV:N/PR:N/UI:N) apunta a T1190. Bypass de restricciones de dominio en email permite acceso no autorizado (T1078) y manipulación de lista de allowlist/denylist (T1565.002).

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)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Forem — Forem^AI

CWEs

CWE-287

References

Raw JSON (NVD)

Show

{
  "id": "CVE-2026-48780",
  "cveTags": [],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-48780",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-06-17T13:49:19.212215Z"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "security-advisories@github.com",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 8.2,
          "attackVector": "NETWORK",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N",
          "integrityImpact": "LOW",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 4.2,
        "exploitabilityScore": 3.9
      }
    ]
  },
  "affected": [
    {
      "source": "security-advisories@github.com",
      "affectedData": [
        {
          "vendor": "forem",
          "product": "forem",
          "versions": [
            {
              "status": "affected",
              "version": "< a2ab6d4"
            }
          ]
        }
      ]
    }
  ],
  "published": "2026-06-16T15:16:41.640",
  "references": [
    {
      "url": "https://github.com/forem/forem/commit/a2ab6d409d2676eb0711ecbd737192043125b437",
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://github.com/forem/forem/security/advisories/GHSA-3g4h-9h37-mpx6",
      "source": "security-advisories@github.com"
    }
  ],
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "type": "Secondary",
      "source": "security-advisories@github.com",
      "description": [
        {
          "lang": "en",
          "value": "CWE-287"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "Forem is open source software for building communities. Prior to commit a2ab6d4, a maliciously crafted email address could allow an attacker to bypass domain allowlist or denylist restrictions and gain access to invite-only forem deployments. The issue is patched as of `a2ab6d4`. As a workaround, some SMTP servers and email delivery providers may drop or refuse to send maliciously crafted email addresses."
    }
  ],
  "lastModified": "2026-06-17T14:17:56.423",
  "sourceIdentifier": "security-advisories@github.com"
}