CVE-2026-44545 Unbounded WebSocket message and frame sizes can cause unauthenticated remote denial of service
Unauthenticated attackers can cause denial of service by sending oversized WebSocket messages due to missing size limits in Daphne.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-44545?
CVE-2026-44545 is a medium-severity denial of service vulnerability in djangoproject daphne, published on 3 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
daphne before 4.2.2 did not pass maxFramePayloadSize or maxMessagePayloadSize to Autobahn's WebSocketServerFactory. Because Autobahn defaults both values to 0 (unlimited), an unauthenticated remote attacker could send arbitrarily large WebSocket messages or frames, causing excessive memory consumption and a denial of service.
Weakness: CWE-770
Which versions are affected by CVE-2026-44545?
3 open source packages ship an affected version, including daphne. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
daphne PyPI | All versions | 4.2.2 |
daphne PyPI | All versions | 4.2.2 |
daphne PyPI | All versions | 4.2.2 |
Products include Djangoproject Daphne.
How do I fix CVE-2026-44545?
Upgrade daphne to 4.2.2 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-44545 being exploited?
There is no known exploitation of CVE-2026-44545 in the wild and no public exploit code.
Other vulnerabilities in djangoproject daphne
Sources
Also known as DEBIAN-CVE-2026-44545, ECHO-f779-f50f-e49e, GHSA-rrc9-mx66-ffcm, PYSEC-2026-213, UBUNTU-CVE-2026-44545.