Low
Mishandling of comma during folding and unicode-encoding of email headers
Type: advisorySources: OSV
During an address list folding when a separating comma ends up on a folded line and that line is to be unicode-encoded then the separator itself is also unicode-encoded. Expected behavior is that the separating comma remains a plan comma. This can result in the address header being misinterpreted by some mail servers.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2025-1795
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 3 Nov 2026, 08:24 UTC · Revision 1
Source evidence
Mishandling of comma during folding and unicode-encoding of email headers
core-osv · Original sourcePublished 28 Feb 2025, 18:59 UTC
During an address list folding when a separating comma ends up on a folded line and that line is to be unicode-encoded then the separator itself is also unicode-encoded. Expected behavior is that the separating comma remains a plan comma. This can result in the address header being misinterpreted by some mail servers.
osv:CVE-2025-1795
Complete source record
{
"id": "fa9921906c77c4d79dbf0434db0a049c5d03131f4f4f86a8eef322d9119aca2d",
"url": "https://osv.dev/vulnerability/CVE-2025-1795",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Mishandling of comma during folding and unicode-encoding of email headers",
"summary": "During an address list folding when a separating comma ends up on a folded line and that line is to be unicode-encoded then the separator itself is also unicode-encoded. Expected behavior is that the separating comma remains a plan comma. This can result in the address header being misinterpreted by some mail servers.",
"evidence": "osv:CVE-2025-1795",
"products": [],
"severity": "low",
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"id": "CVE-2025-1795",
"aliases": [
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"BIT-python-2025-1795",
"BIT-python-min-2025-1795",
"CVE-2025-1795",
"PSF-2025-3"
],
"metrics": [
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N"
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"modified": "2026-10-28T02:30:27.178078337Z",
"provider": "osv",
"references": [
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