VulnerabilityAnalyzed

CVE-2026-44546

An attacker can exploit this parser differential to inject additional headers into the ASGI scope passed to the application. daphne now rejects requests with these bytes in any header value with a 400 response.

MEDIUM 5.3EPSS 0.17%

Does this matter?

Lower severity and a low EPSS score (0.17%). Track it; it rarely justifies an emergency change on its own.

Description

daphne before 4.2.2 reconstructs a raw HTTP request from Twisted's parsed headers and feeds it to autobahn for WebSocket handshake processing. Twisted does not treat \x0b, \x0c, \x1c, \x1d, \x1e, or \x85 as header line separators, but autobahn decodes header values to str and calls splitlines(). An attacker can exploit this parser differential to inject additional headers into the ASGI scope passed to the application. daphne now rejects requests with these bytes in any header value with a 400 response.

CVSS 3.1: 5.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
EPSS: 0.17% probability · 7th percentile
CISA KEV: Not listed
Weakness: CWE-444
Affected: djangoproject/daphne
Source: 6a34fbeb-21d4-45e7-8e0a-62b95bc12c92

References

https://github.com/django/daphne/blob/main/CHANGELOG.txtRelease Notes

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.