CVE-2026-48780 (GCVE-0-2026-48780)
Vulnerability from cvelistv5 – Published: 2026-06-16 14:10 – Updated: 2026-06-17 13:49
VLAI
EPSS
VEX
Title
Forem vulnerable to bypass of email address domain restrictions
Summary
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.
Severity
8.2 (High)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-17 13:49 UTC
CWE
- CWE-287 - Improper Authentication
Assigner
GitHub_M
CNA
References
2 references
| URL | Tags |
|---|---|
| https://github.com/forem/forem/security/advisorie… | x_refsource_CONFIRM |
| https://github.com/forem/forem/commit/a2ab6d409d2… | x_refsource_MISC |
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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.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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