CVE-2026-30227

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Source
https://cve.org/CVERecord?id=CVE-2026-30227
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-30227.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-30227
Aliases
Published
2026-03-06T21:07:49.691Z
Modified
2026-03-14T15:06:00.921763Z
Severity
  • 6.9 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N CVSS Calculator
Summary
MimeKit: CRLF Injection in Quoted Local-Part Enables SMTP Command Injection and Email Forgery
Details

MimeKit is a C# library which may be used for the creation and parsing of messages using the Multipurpose Internet Mail Extension (MIME), as defined by numerous IETF specifications. Prior to version 4.15.1, a CRLF injection vulnerability in MimeKit allows an attacker to embed \r\n into the SMTP envelope address local-part (when the local-part is a quoted-string). This is non-compliant with RFC 5321 and can result in SMTP command injection (e.g., injecting additional RCPT TO / DATA / RSET commands) and/or mail header injection, depending on how the application uses MailKit/MimeKit to construct and send messages. The issue becomes exploitable when the attacker can influence a MailboxAddress (MAIL FROM / RCPT TO) value that is later serialized to an SMTP session. RFC 5321 explicitly defines the SMTP mailbox local-part grammar and does not permit CR (13) or LF (10) inside Quoted-string (qtextSMTP and quoted-pairSMTP ranges exclude control characters). SMTP commands are terminated by <CRLF>, making CRLF injection in command arguments particularly dangerous. This issue has been patched in version 4.15.1.

Database specific 
{
    "cwe_ids": [
        "CWE-93"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/30xxx/CVE-2026-30227.json",
    "cna_assigner": "GitHub_M"
}
References

Affected packages

Git / github.com/jstedfast/mimekit

Affected ranges

Type
GIT
Repo
https://github.com/jstedfast/mimekit
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
5c79dcc7c7c6c238aec40747ecf7481393a3d04e

Affected versions

1.*
1.0.0
1.0.1
1.0.10
1.0.11
1.0.12
1.0.13
1.0.14
1.0.15
1.0.2
1.0.3
1.0.4
1.0.5
1.0.6
1.0.7
1.0.8
1.0.9
1.10.0
1.10.1
1.12.0
1.14.0
1.14.1
1.16.0
1.16.1
1.16.2
1.18.0
1.18.1
1.2.0
1.2.1
1.2.10
1.2.11
1.2.12
1.2.13
1.2.14
1.2.15
1.2.16
1.2.17
1.2.18
1.2.19
1.2.2
1.2.20
1.2.21
1.2.22
1.2.23
1.2.24
1.2.25
1.2.3
1.2.4
1.2.5
1.2.6
1.2.7
1.2.8
1.2.9
1.20.0
1.22.0
1.4.0
1.4.1
1.4.2
1.6.0
1.8.0
2.*
2.0.0
2.0.1
2.0.2
2.0.3
2.0.4
2.0.5
2.0.6
2.0.7
2.1.0
2.1.1
2.1.2
2.1.3
2.1.4
2.1.5
2.1.5.1
2.10.0
2.10.1
2.11.0
2.12.0
2.13.0
2.14.0
2.15.0
2.15.1
2.2.0
2.3.0
2.3.1
2.3.2
2.4.0
2.4.1
2.5.0
2.5.1
2.5.2
2.6.0
2.7.0
2.8.0
2.9.1
2.9.2
3.*
3.0.0
3.1.0
3.1.1
3.2.0
3.3.0
3.4.0
3.4.1
3.4.2
3.4.3
3.5.0
3.6.0
3.6.1
4.*
4.0.0
4.1.0
4.10.0
4.11.0
4.12.0
4.13.0
4.14.0
4.15.0
4.2.0
4.3.0
4.4.0
4.5.0
4.6.0
4.7.0
4.7.1
4.8.0
4.9.0

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-30227.json"