CVE-2026-44545: Unbounded WebSocket message and frame sizes can cause unauthenticated remote denial of service
Vulnerability summary
CVE-2026-44545 is a high (CVSS 7.5) vulnerability in djangoproject daphne. EPSS estimates a 0.33% chance of exploitation in the next 30 days, higher than 25.9% of scored vulnerabilities.
Not severe (CVSS 5.3, network access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 3Timeline
- 03-06-2026PublishedVulnerability first disclosed.
- 03-06-2026Last modifiedVulnerability information updated.
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.
CVSS metrics
7 scores · 7 sources · 1 version- CVE.orgCNA5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:LDiffers
- OSV · PypiEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · UbuntuEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · ChainguardEcosystem advisory · calculated5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:LDiffers
- OSV · AlpineEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.33%
Chance of exploitation in the next 30 days
Percentile
26%
Versus all other CVEs
30-day change
Decrease -0.24 pp
From 0.57% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Alpine1 product
- py3-daphne< 4.2.3-r0
Chainguard1 product
- awxAll versions (No fix recorded)
Debian1 product
- python-daphneAll versions (No fix recorded) | < 4.1.2-2+deb13u1 | < 4.2.2-0.1
Djangoproject1 product
- daphne≥ 4.2.0, ≤ 4.2.1 | < 4.2.2
PyPI1 product
- daphne< 4.2.2
Ubuntu1 product
- python-daphneAll versions (No fix recorded)
6 vendors · 6 products
References
12 links
- github.com/django/daphnePACKAGE
Show all 12 references
- pypi.org/project/daphne/PACKAGE