CVE Explorer

CVE-2026-44436

Quicly is an IETF QUIC protocol implementation intended primarily for use within the H2O HTTP server. Prior to commit 8b178e6, Quicly is vulnerable to a Denial of Service attack through connection state corruption. In QUIC Invariants, the maximum length of a Connection ID is 255 bytes, while QUIC version 1 further restricts the maximum to 20 bytes. Quicly implements QUIC version 1 and therefore its CID buffers are limited to 20 bytes. However, to be able to respond to unknown versions of QUIC, i

Lifecycle PUBLISHED1 preserved revisionFact urn:baitaphish:canonical-cve-fact-revision:v2:bb33b9930e8abd5028da6a73819bf9825a21496c57cb4f17eb3e40e75427ffe6

Known exploited

Not asserted

Disputed

Stale source

Conflicts

Preserved source conflicts

No provider value was silently selected as the winner.

cwe · 2 assertions

{"cweId":"CWE-787","description":"CWE-787: Out-of-bounds Write","lang":"en","type":"CWE"}

cve_program_cvelist_v5cwe
urn:baitaphish:normalized-source-record:v2:89d44097a0658f88d76ec831f296995b8c7969d52b97f1b045113d7a2dc39bcd · sha256:5513d5b282fdf40c… · /containers/cna/problemTypes/1/descriptions/0

{"cweId":"CWE-120","description":"CWE-120: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')","lang":"en","type":"CWE"}

cve_program_cvelist_v5cwe
urn:baitaphish:normalized-source-record:v2:89d44097a0658f88d76ec831f296995b8c7969d52b97f1b045113d7a2dc39bcd · sha256:5513d5b282fdf40c… · /containers/cna/problemTypes/0/descriptions/0

Affected products and versions

1 source assertion

{"product":"quicly","vendor":"h2o","versions":[{"status":"affected","version":"< 8b178e6"}]}

cve_program_cvelist_v5affected
urn:baitaphish:normalized-source-record:v2:89d44097a0658f88d76ec831f296995b8c7969d52b97f1b045113d7a2dc39bcd · sha256:5513d5b282fdf40c… · /containers/cna/affected/0

Provider-owned CVSS observations

1 source assertion

{"metric":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"metric_type":"cvssV3_1"}

cve_program_cvelist_v5cvss
urn:baitaphish:normalized-source-record:v2:89d44097a0658f88d76ec831f296995b8c7969d52b97f1b045113d7a2dc39bcd · sha256:5513d5b282fdf40c… · /containers/cna/metrics/0/cvssV3_1

CWE assertions

2 source assertions

{"cweId":"CWE-787","description":"CWE-787: Out-of-bounds Write","lang":"en","type":"CWE"}

cve_program_cvelist_v5cwe
urn:baitaphish:normalized-source-record:v2:89d44097a0658f88d76ec831f296995b8c7969d52b97f1b045113d7a2dc39bcd · sha256:5513d5b282fdf40c… · /containers/cna/problemTypes/1/descriptions/0

{"cweId":"CWE-120","description":"CWE-120: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')","lang":"en","type":"CWE"}

cve_program_cvelist_v5cwe
urn:baitaphish:normalized-source-record:v2:89d44097a0658f88d76ec831f296995b8c7969d52b97f1b045113d7a2dc39bcd · sha256:5513d5b282fdf40c… · /containers/cna/problemTypes/0/descriptions/0

Source references

2 source assertions

{"name":"https://github.com/h2o/quicly/commit/8b178e692c51a3b1031612ef89f03a53aac63c15","tags":["x_refsource_MISC"],"url":"https://github.com/h2o/quicly/commit/8b178e692c51a3b1031612ef89f03a53aac63c15"}

cve_program_cvelist_v5reference
urn:baitaphish:normalized-source-record:v2:89d44097a0658f88d76ec831f296995b8c7969d52b97f1b045113d7a2dc39bcd · sha256:5513d5b282fdf40c… · /containers/cna/references/1

{"name":"https://github.com/h2o/quicly/security/advisories/GHSA-v55w-59qx-2v78","tags":["x_refsource_CONFIRM"],"url":"https://github.com/h2o/quicly/security/advisories/GHSA-v55w-59qx-2v78"}

cve_program_cvelist_v5reference
urn:baitaphish:normalized-source-record:v2:89d44097a0658f88d76ec831f296995b8c7969d52b97f1b045113d7a2dc39bcd · sha256:5513d5b282fdf40c… · /containers/cna/references/0

Attribution and limitations

CVE Program CVEList V5: Reproduce the MITRE copyright designation and CVE license in copies. Source →

Provider severity values are preserved separately. Baitaphish does not convert them into a risk rating, infer affected products, or treat EPSS as observed exploitation.

← Back to CVE Explorer