CVE-2026-44433 (GCVE-0-2026-44433)
Vulnerability from cvelistv5
Published
2026-07-16 22:23
Modified
2026-07-17 18:06
Severity ?
VLAI Severity ?
EPSS score ?
CWE
Summary
Quicly is an IETF QUIC protocol implementation intended primarily for use within the H2O HTTP server. Prior to commit 8b178e6, an adversarial peer could send a STREAM frame carrying just one byte at the largest offset being permitted to obtain additional flow control credit, which under certain circumstances could lead to a Denial of Service. Assuming the application prepares a receive buffer for storing all data that arrive out-of-order, up to the largest offset being received, this behavior could lead to the application allocating large amount of memory with the peer sending only a handful of packets, resulting in memory exhaustion. In addition to the receive buffer allocation strategy, the severity of this vulnerability depends on how the application controls the stream concurrency. In case of the H2O HTTP server, under its default setting, this bug increases the maximum amount of memory allocated per connection by about 4 times. This issue has been fixed by commit 8b178e6.
References
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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