DEBIAN-CVE-2026-84378
HTTPX2 is a next generation HTTP client for Python. From 2.5.0 until 2.10.0, the HTTPX2 Server-Sent Events parser in src/httpx2/httpx2/_sse.py repeatedly copies and rescans buffered text in _SSELineDecoder.decode() when an attacker-controlled or compromised SSE endpoint splits one unterminated line across many response chunks. The behavior affects httpx2.Client.sse() and httpx2.AsyncClient.sse(), and the total processing work grows quadratically with the line length, allowing a crafted stream to consume excessive CPU and block a synchronous worker or asynchronous event loop. This issue is fixed in version 2.10.0.
DEBIAN-CVE-2026-84378
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: osv:DEBIAN-CVE-2026-84378
python-httpx2
Source reference: /affected/0/package/name
- Affected versions
- 2.4.0-1
Source reference:
/affected/0/versions2.5.0-1Source reference:
/affected/0/versions - Fixed versions
- 2.12.0-1
Source reference:
/affected/0/ranges - Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.12.0-1"
}
]
}
],
"package": {
"name": "python-httpx2",
"purl": "pkg:deb/debian/python-httpx2?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"2.4.0-1",
"2.5.0-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-84378.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
]Publisher severity
No explicit severity was provided.
- Event
- #58238 · Revision 1
- Added to Heist Feed
- Publisher date