{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-105297",
        "assignerOrgId": "a22f1246-ba21-4bb4-a601-ad51614c1513",
        "state": "PUBLISHED",
        "assignerShortName": "cloudflare",
        "dateReserved": "2026-10-05T04:18:56.102Z",
        "datePublished": "2026-10-20T00:40:27.300Z",
        "dateUpdated": "2026-10-20T19:20:35.542Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "a22f1246-ba21-4bb4-a601-ad51614c1513",
                "shortName": "cloudflare",
                "dateUpdated": "2026-10-20T00:40:27.300Z"
            },
            "title": "Pingora HTTP/2 server memory exhaustion through unbounded default header-list and concurrent-stream limits",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "cweId": "CWE-770",
                            "description": "CWE-770 Allocation of resources without limits or throttling",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "vendor": "Cloudflare",
                    "product": "https://github.com/cloudflare/pingora",
                    "repo": "https://github.com/cloudflare/pingora",
                    "versions": [
                        {
                            "status": "affected",
                            "version": "0.1.0",
                            "lessThan": "0.8.1",
                            "versionType": "semver"
                        }
                    ],
                    "defaultStatus": "unaffected"
                }
            ],
            "descriptions": [
                {
                    "lang": "en",
                    "value": "Summary\n\n\n\nBefore version 0.8.1, Pingora's HTTP/2 server used the h2 crate's default limits unless the application set its own 16 MiB decoded header-list size and no limit on concurrent streams. A remote, unauthenticated client can send 1-byte HPACK references to a near-empty header, making the server allocate hundreds of thousands of header fields per stream across an unlimited number of streams on one connection, and use HTTP/2 flow control to keep those streams open. This can exhaust memory and degrade or terminate the Pingora process.\n\n\n\n\nImpact\n\n\n\nRemote, unauthenticated denial of service against any Pingora service that terminates HTTP/2 (h2 or h2c) without explicitly setting max_header_list_size and max_concurrent_streams. The reporter showed that a single connection could get a Pingora process with a 2 GiB memory limit OOM-killed.\n\n\n\n\nNote that Cloudflare CDN customers were unaffected, as internal Pingora services at Cloudflare do not have HTTP/2 clients.\n\n\n\nMitigation:\n\n  *  \n\nUpgrade to pingora 0.8.1 or later (fix:  https://github.com/cloudflare/pingora/commit/d193c8d49b8b7c1c1ede93183759caa4f6906bbd ). When no H2Options are supplied, Pingora now advertises and enforces a 64 KiB decoded header-list limit and at most 100 concurrent streams per connection.\n\n\n  *  \n\nApplications that supply their own H2Options are not covered by these defaults and must set max_header_list_size and max_concurrent_streams explicitly (this also works on versions before 0.8.1), or, on 0.8.1 and later, start from pingora_core::protocols::http::v2::server::default_h2_options(). H2Options::default() does not include these limits.",
                    "supportingMedia": [
                        {
                            "type": "text/html",
                            "base64": false,
                            "value": "<p>Summary</p><p>Before version 0.8.1, Pingora's HTTP/2 server used the h2 crate's default limits unless the application set its own 16 MiB decoded header-list size and no limit on concurrent streams. A remote, unauthenticated client can send 1-byte HPACK references to a near-empty header, making the server allocate hundreds of thousands of header fields per stream across an unlimited number of streams on one connection, and use HTTP/2 flow control to keep those streams open. This can exhaust memory and degrade or terminate the Pingora process.</p><br><p>Impact</p><p>Remote, unauthenticated denial of service against any Pingora service that terminates HTTP/2 (h2 or h2c) without explicitly setting max_header_list_size and max_concurrent_streams. The reporter showed that a single connection could get a Pingora process with a 2 GiB memory limit OOM-killed.</p><br><p>Note that Cloudflare CDN customers were unaffected, as internal Pingora services at Cloudflare do not have HTTP/2 clients.</p><p>Mitigation:</p><ul><li><p>Upgrade to pingora 0.8.1 or later (fix: <a href=\"https://github.com/cloudflare/pingora/commit/d193c8d49b8b7c1c1ede93183759caa4f6906bbd\">https://github.com/cloudflare/pingora/commit/d193c8d49b8b7c1c1ede93183759caa4f6906bbd</a>). When no H2Options are supplied, Pingora now advertises and enforces a 64 KiB decoded header-list limit and at most 100 concurrent streams per connection.</p></li><li><p>Applications that supply their own H2Options are not covered by these defaults and must set max_header_list_size and max_concurrent_streams explicitly (this also works on versions before 0.8.1), or, on 0.8.1 and later, start from pingora_core::protocols::http::v2::server::default_h2_options(). H2Options::default() does not include these limits.</p></li></ul>"
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://github.com/cloudflare/pingora"
                }
            ],
            "metrics": [
                {
                    "format": "CVSS",
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "GENERAL"
                        }
                    ],
                    "cvssV3_1": {
                        "version": "3.1",
                        "attackVector": "NETWORK",
                        "attackComplexity": "LOW",
                        "privilegesRequired": "NONE",
                        "userInteraction": "NONE",
                        "scope": "UNCHANGED",
                        "confidentialityImpact": "NONE",
                        "integrityImpact": "NONE",
                        "availabilityImpact": "HIGH",
                        "baseSeverity": "HIGH",
                        "baseScore": 7.5,
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
                    }
                }
            ],
            "solutions": [
                {
                    "lang": "en",
                    "value": "Mitigation:\n\n  *  \n\nUpgrade to pingora 0.8.1 or later (fix:  https://github.com/cloudflare/pingora/commit/d193c8d49b8b7c1c1ede93183759caa4f6906bbd ). When no H2Options are supplied, Pingora now advertises and enforces a 64 KiB decoded header-list limit and at most 100 concurrent streams per connection.\n\n\n  *  \n\nApplications that supply their own H2Options are not covered by these defaults and must set max_header_list_size and max_concurrent_streams explicitly (this also works on versions before 0.8.1), or, on 0.8.1 and later, start from pingora_core::protocols::http::v2::server::default_h2_options(). H2Options::default() does not include these limits.",
                    "supportingMedia": [
                        {
                            "type": "text/html",
                            "base64": false,
                            "value": "<b><p>Mitigation:</p><ul><li><p>Upgrade to pingora 0.8.1 or later (fix: <a href=\"https://github.com/cloudflare/pingora/commit/d193c8d49b8b7c1c1ede93183759caa4f6906bbd\">https://github.com/cloudflare/pingora/commit/d193c8d49b8b7c1c1ede93183759caa4f6906bbd</a>). When no H2Options are supplied, Pingora now advertises and enforces a 64 KiB decoded header-list limit and at most 100 concurrent streams per connection.</p></li><li><p>Applications that supply their own H2Options are not covered by these defaults and must set max_header_list_size and max_concurrent_streams explicitly (this also works on versions before 0.8.1), or, on 0.8.1 and later, start from pingora_core::protocols::http::v2::server::default_h2_options(). H2Options::default() does not include these limits.</p></li></ul></b>"
                        }
                    ]
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "value": "Reported by jro-calif (GitHub)",
                    "type": "reporter"
                }
            ],
            "source": {
                "discovery": "UNKNOWN"
            },
            "x_generator": {
                "engine": "Vulnogram 1.0.5"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-10-20T19:20:25.097096Z",
                                "id": "CVE-2026-105297",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "yes"
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                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
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                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-10-20T19:20:35.542Z"
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        ]
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}