{"id":"CVE-2026-105297","aliases":["RUSTSEC-2026-0389","GHSA-7gpj-mj4q-x62x"],"title":"Pingora HTTP/2 server memory exhaustion through unbounded default header-list and concurrent-stream limits","summary":"Pingora HTTP/2 server memory exhaustion through unbounded default header-list and concurrent-stream limits","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","vendor":"pingora-core","product":"pingora-core","ecosystem":"rust","affected":["pingora-core >= 0.0.0-0, < 0.8.1"],"patched":["pingora-core 0.8.1"],"published":"2026-10-20","updated":"2026-10-26","sourceUpdated":"2026-10-26T11:15:11.357540777Z","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/RUSTSEC-2026-0389","references":[{"url":"https://crates.io/crates/pingora-core"},{"url":"https://rustsec.org/advisories/RUSTSEC-2026-0389.html"},{"url":"https://github.com/cloudflare/pingora/commit/d193c8d49b8b7c1c1ede93183759caa4f6906bbd"},{"url":"https://github.com/cloudflare/pingora"}],"tags":["osv","rust","cve.org"],"epss":0.00429,"epssPercentile":0.37011,"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"partial","timestamp":"2026-10-20T19:20:25.097096Z"},"cvssSource":"cna","cwe":["CWE-770"],"ingestedAt":"2026-10-20T01:49:42.629Z","slug":"CVE-2026-105297","body":"## Overview\n\nPingora versions prior to 0.8.1 used the h2 crate's default HTTP/2 server limits, a 16 MiB decoded header-list size and no limit on concurrent streams, unless the application set its own. 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\nThis affects 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\nThis flaw was corrected in 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. Users should upgrade to Pingora >= 0.8.1. Applications that supply their own `H2Options` are not covered by these defaults and must set `max_header_list_size` and `max_concurrent_streams` explicitly, or start from `pingora_core::protocols::http::v2::server::default_h2_options()`. `H2Options::default()` does not include these limits.\n\nNote: Cloudflare CDN customers were unaffected, as internal Pingora services at Cloudflare do not have HTTP/2 clients.\n\n## Affected packages\n\n- `pingora-core >= 0.0.0-0, < 0.8.1`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `pingora-core 0.8.1`","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}