CVE-2026-44435
Quicly: Remote Denial of Service via assertion failure when CRYPTO stream handshake data exceeds 32KB
Description
Quicly is an IETF QUIC protocol implementation intended primarily for use within the H2O HTTP server. Prior to commit 937d0e9, an assertion failure is raised when the total number of valid handshake messages received over a CRYPTO stream of a single packet number space exceeds 32KB, causing a Denial of Service. This issue has been fixed by commit 937d0e9.
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:LAttack ComplexityLow
PR:NPrivileges RequiredNone
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:NConfidentialityNone
I:NIntegrityNone
A:HAvailabilityHigh
Weaknesses
Affected Products
h2o
oss-projectaka quicly, h2o web server, picotls
Exploitability
Official Patch Available
Attack Graph
Products CVE Techniques Tactics
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MITRE ATT&CK
1 technique Impact
References
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