CVE-2026-90467

NVD: aiosmtplib before 5.1.3 fails to properly validate email addresses supplied by callers, allowing attackers to inject ESMTP parameters into MAIL FROM and RCPT TO command lines. NVD: Attackers can craft malicious addresses containing spaces and angle brackets to append parameters like AUTH, NOTIFY, or ORCPT to envelope commands, forging authenticated identities or forcing delivery notifications to third parties. OSV: aiosmtplib before 5.1.3 ESMTP Parameter Injection via unvalidated addresses

Source-published summary

NVD: aiosmtplib before 5.1.3 fails to properly validate email addresses supplied by callers, allowing attackers to inject ESMTP parameters into MAIL FROM and RCPT TO command lines. NVD: Attackers can craft malicious addresses containing spaces and angle brackets to append parameters like AUTH, NOTIFY, or ORCPT to envelope commands, forging authenticated identities or forcing delivery notifications to third parties. OSV: aiosmtplib before 5.1.3 ESMTP Parameter Injection via unvalidated addresses

Possible impact

This medium severity issue needs human triage to confirm exposure, affected versions, and vendor guidance for defensive exposure review.

Affected context

Affected product or version requires source confirmation.

Remediation / advisory

Remediation reference present; patch status requires confirmation in the linked advisory.

Why it matters

This medium severity issue needs human triage to confirm exposure, affected versions, and vendor guidance for defensive exposure review.; CVSS 6.3 (MEDIUM); EPSS percentile 14; not listed in KEV; Remediation reference present; patch status requires confirmation in the linked advisory; sources: NVD, OSV.

What to verify

Confirm affected product/version, vendor advisory, patch or mitigation, and exposure.

Exposure hint

exposure unknown

Impact tags

Urgency reasons

Source-derived note

Summary derived from NVD / OSV description; unsafe procedural detail is not shown.

Redaction metadata

source summary used

True

fallback summary used

False

unsafe procedural detail present

false

raw source displayed

false

public summary redacted

true

Remediation handoff

Public-safe static handoff for human/Codex remediation planning. Scan, patch, external execution, and auto remediation are disabled.

Safety note

This radar shows source-published defensive context only. Exploit procedures, exploit strings, scanner commands, and auto-remediation are not provided.

Official references

• https://nvd.nist.gov/vuln/detail/CVE-2026-90467
• https://osv.dev/vulnerability/CVE-2026-90467