{"api_version":"1","generated_at":"2026-07-16T12:08:58+00:00","cve":"CVE-2026-12523","urls":{"html":"https://cve.report/CVE-2026-12523","api":"https://cve.report/api/cve/CVE-2026-12523.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-12523","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-12523"},"summary":{"title":"Resource exhaustion in quiche HTTP/3 and QPACK layers","description":"Summary\n\n\n\nCloudflare quiche's HTTP/3 layer was discovered to be vulnerable to resource exhaustion (i.e., memory) by means of specially crafted HTTP/3 frames.\n\n\n\n\nImpact\n\n\n\nHTTP/3 defines multiple frame types to support HTTP message exchanges and connection management. Each frame has a length and a payload whose length depends on the frame type. quiche was found to be vulnerable when parsing some frame types to pre-allocating memory based on the declared length. An attacker would not need to send the number of declared bytes to trigger this issue.\n\n\n\nIn addition, quiche was found to not apply QPACK decompression limits correctly. This could allow an attacker to send specially crafted HEADERS frames that would cause more memory commitment than otherwise advertised by MAX_FIELD_SECTION_SIZE (configured by set_max_field_section_size()).\n\n\n\n\n\n\nMitigation:\n\n  *  \n\nUsers are requested to upgrade to quiche 0.29.3 which is the earliest version containing the fix for this issue.\n\n\n\n\n\n\n\n\n\nCredits: Disclosed responsibly by Sébastien Féry","state":"PUBLISHED","assigner":"cloudflare","published_at":"2026-07-14 16:16:45","updated_at":"2026-07-15 18:16:44"},"problem_types":["CWE-400","CWE-400 CWE-400 Uncontrolled Resource Consumption"],"metrics":[{"version":"3.1","source":"cna@cloudflare.com","type":"Secondary","score":"7.5","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"CVSS","score":"7.5","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","data":{"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"}}],"references":[{"url":"https://github.com/cloudflare/quiche/security/advisories/GHSA-4fgf-9xrr-88gf","name":"https://github.com/cloudflare/quiche/security/advisories/GHSA-4fgf-9xrr-88gf","refsource":"cna@cloudflare.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-12523","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-12523","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Cloudflare","product":"quiche","version":"affected 0.1.0 0.29.3 semver","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[{"source":"CNA","value":"Sébastien Féry","lang":"en"}],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"12523","cve":"CVE-2026-12523","epss":"0.002920000","percentile":"0.210970000","score_date":"2026-07-15","updated_at":"2026-07-16 00:08:43"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"adp":[{"metrics":[{"other":{"content":{"id":"CVE-2026-12523","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","timestamp":"2026-07-15T14:08:33.441723Z","version":"2.0.3"},"type":"ssvc"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-400","description":"CWE-400 Uncontrolled Resource Consumption","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-07-15T17:47:52.441Z","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP"},"title":"CISA ADP Vulnrichment"}],"cna":{"affected":[{"defaultStatus":"unaffected","product":"quiche","vendor":"Cloudflare","versions":[{"lessThan":"0.29.3","status":"affected","version":"0.1.0","versionType":"semver"}]}],"credits":[{"lang":"en","type":"reporter","value":"Sébastien Féry"}],"descriptions":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"<p>Summary</p><p>Cloudflare quiche's HTTP/3 layer was discovered to be vulnerable to resource exhaustion (i.e., memory) by means of specially crafted HTTP/3 frames.</p><br><div><p>Impact</p><p>HTTP/3 defines multiple frame types to support HTTP message exchanges and connection management. Each frame has a length and a payload whose length depends on the frame type. quiche was found to be vulnerable when parsing some frame types to pre-allocating memory based on the declared length. An attacker would not need to send the number of declared bytes to trigger this issue.</p><p>In addition, quiche was found to not apply QPACK decompression limits correctly. This could allow an attacker to send specially crafted HEADERS frames that would cause more memory commitment than otherwise advertised by MAX_FIELD_SECTION_SIZE (configured by set_max_field_section_size()).</p><br></div><div><p>Mitigation:</p><ul><li><p>Users are requested to upgrade to quiche 0.29.3 which is the earliest version containing the fix for this issue.</p></li></ul><div><br></div></div><div><b>Credits: </b>Disclosed responsibly by Sébastien Féry&nbsp;</div>"}],"value":"Summary\n\n\n\nCloudflare quiche's HTTP/3 layer was discovered to be vulnerable to resource exhaustion (i.e., memory) by means of specially crafted HTTP/3 frames.\n\n\n\n\nImpact\n\n\n\nHTTP/3 defines multiple frame types to support HTTP message exchanges and connection management. Each frame has a length and a payload whose length depends on the frame type. quiche was found to be vulnerable when parsing some frame types to pre-allocating memory based on the declared length. An attacker would not need to send the number of declared bytes to trigger this issue.\n\n\n\nIn addition, quiche was found to not apply QPACK decompression limits correctly. This could allow an attacker to send specially crafted HEADERS frames that would cause more memory commitment than otherwise advertised by MAX_FIELD_SECTION_SIZE (configured by set_max_field_section_size()).\n\n\n\n\n\n\nMitigation:\n\n  *  \n\nUsers are requested to upgrade to quiche 0.29.3 which is the earliest version containing the fix for this issue.\n\n\n\n\n\n\n\n\n\nCredits: Disclosed responsibly by Sébastien Féry"}],"metrics":[{"cvssV3_1":{"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"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"providerMetadata":{"dateUpdated":"2026-07-14T15:51:28.886Z","orgId":"a22f1246-ba21-4bb4-a601-ad51614c1513","shortName":"cloudflare"},"references":[{"url":"https://github.com/cloudflare/quiche/security/advisories/GHSA-4fgf-9xrr-88gf"}],"source":{"discovery":"UNKNOWN"},"title":"Resource exhaustion in quiche HTTP/3 and QPACK layers","x_generator":{"engine":"Vulnogram 1.0.2"}}},"cveMetadata":{"assignerOrgId":"a22f1246-ba21-4bb4-a601-ad51614c1513","assignerShortName":"cloudflare","cveId":"CVE-2026-12523","datePublished":"2026-07-14T15:51:28.886Z","dateReserved":"2026-06-17T13:35:37.498Z","dateUpdated":"2026-07-15T17:47:52.441Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-07-14 16:16:45","lastModifiedDate":"2026-07-15 18:16:44","problem_types":["CWE-400","CWE-400 CWE-400 Uncontrolled Resource Consumption"],"metrics":{"cvssMetricV31":[{"source":"cna@cloudflare.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":3.9,"impactScore":3.6}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-07-15T14:08:33.441723Z","id":"CVE-2026-12523","options":[{"exploitation":"none"},{"automatable":"yes"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"12523","Ordinal":"1","Title":"Resource exhaustion in quiche HTTP/3 and QPACK layers","CVE":"CVE-2026-12523","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"12523","Ordinal":"1","NoteData":"Summary\n\n\n\nCloudflare quiche's HTTP/3 layer was discovered to be vulnerable to resource exhaustion (i.e., memory) by means of specially crafted HTTP/3 frames.\n\n\n\n\nImpact\n\n\n\nHTTP/3 defines multiple frame types to support HTTP message exchanges and connection management. Each frame has a length and a payload whose length depends on the frame type. quiche was found to be vulnerable when parsing some frame types to pre-allocating memory based on the declared length. An attacker would not need to send the number of declared bytes to trigger this issue.\n\n\n\nIn addition, quiche was found to not apply QPACK decompression limits correctly. This could allow an attacker to send specially crafted HEADERS frames that would cause more memory commitment than otherwise advertised by MAX_FIELD_SECTION_SIZE (configured by set_max_field_section_size()).\n\n\n\n\n\n\nMitigation:\n\n  *  \n\nUsers are requested to upgrade to quiche 0.29.3 which is the earliest version containing the fix for this issue.\n\n\n\n\n\n\n\n\n\nCredits: Disclosed responsibly by Sébastien Féry","Type":"Description","Title":"Resource exhaustion in quiche HTTP/3 and QPACK layers"}]}}}