MediumFix available
python3 — security advisory
The email module of Python through 3.11.3 incorrectly parses e-mail addresses that contain a special character. The wrong portion of an RFC2822 header is identified as the value of the addr-spec. In some applications, an attacker can bypass a protection mechanism in which application access is granted only after verifying receipt of e-mail to a specific domain (e.g., only @company.example.com addresses may be used for signup). This occurs in email/_parseaddr.py in recent versions of Python.
- Products
- python3
- Affected versions
- Not specified
- Fixed versions
- 3.10.15-r0, 3.11.10-r0, 3.12.6-r0
- CVEs
- CVE-2023-27043
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 14:55 UTC · Revision 1
Source evidence
The email module of Python through 3.11.3 incorrectly parses e-mail addresses that contain a special character. The wrong portion of an RFC2822 header is identified as the value of the addr-spec. In some applications, an attacker can bypass a protection mechanism in which application access is granted only after verifying receipt of e-mail to a specific domain (e.g., only @company.example.com addresses may be used for signup). This occurs in email/_parseaddr.py in recent versions of Python.
osv:ALPINE-CVE-2023-27043
python3
Fixed versions: 3.10.15-r0
python3
Fixed versions: 3.11.10-r0
python3
Fixed versions: 3.11.10-r0
python3
Fixed versions: 3.12.6-r0
python3
Fixed versions: 3.12.6-r0
python3
Fixed versions: 3.12.6-r0
python3
Fixed versions: 3.12.6-r0
python3
Fixed versions: 3.12.6-r0
Complete source record
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"url": "https://osv.dev/vulnerability/ALPINE-CVE-2023-27043",
"method": "structured",
"payload": {
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"summary": "The email module of Python through 3.11.3 incorrectly parses e-mail addresses that contain a special character. The wrong portion of an RFC2822 header is identified as the value of the addr-spec. In some applications, an attacker can bypass a protection mechanism in which application access is granted only after verifying receipt of e-mail to a specific domain (e.g., only @company.example.com addresses may be used for signup). This occurs in email/_parseaddr.py in recent versions of Python.",
"evidence": "osv:ALPINE-CVE-2023-27043",
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],
"modified": "2026-10-26T17:17:58.614243367Z",
"provider": "osv",
"upstream": [
"CVE-2023-27043"
],
"references": [
"https://security.alpinelinux.org/vuln/CVE-2023-27043"
]
},
"related_cves": [
{
"value": "CVE-2023-27043",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 454399,
"published_at": "2023-04-19T00:15:07.973+00:00"
}