{"id":"CVE-2026-35457","aliases":["EUVD-2026-19650","GHSA-v5hw-cv9c-rpg7"],"status":"published","title":"libp2p-rust has unbounded rendezvous DISCOVER cookies enable remote memory exhaustion","description":"libp2p-rust is the official rust language Implementation of the libp2p networking stack. Prior to 0.17.1, the rendezvous server stores pagination cookies without bounds. An unauthenticated peer can repeatedly issue DISCOVER requests and force unbounded memory growth. This vulnerability is fixed in 0.17.1.","severity":{"version":"3.1","score":8.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00296,"percentile":0.22541,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-770"],"published":"2026-04-04T06:34:29Z","modified":"2026-06-17T10:40:37Z","fixes":[{"ecosystem":"crates.io","package":"libp2p-rendezvous","fixed_in":["0.17.1"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"crates.io","package":"libp2p-rendezvous","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.17.1"}]}]},{"source":"osv","ecosystem":"crates.io","package":"libp2p-rendezvous","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"0.17.1"}]}]}],"products":[{"vendor":"libp2p","product":"rust-libp2p"},{"vendor":"protocol","product":"libp2p"}],"references":[{"url":"https://github.com/libp2p/rust-libp2p/security/advisories/GHSA-v5hw-cv9c-rpg7","tags":["x_refsource_CONFIRM","Exploit","Vendor Advisory","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-35457","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-v5hw-cv9c-rpg7"},{"url":"https://github.com/libp2p/rust-libp2p","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-35457","title":"libp2p-rust has unbounded rendezvous DISCOVER cookies enable remote memory exhaustion","description":"libp2p-rust is the official rust language Implementation of the libp2p networking stack. Prior to 0.17.1, the rendezvous server stores pagination cookies without bounds. An unauthenticated peer can repeatedly issue DISCOVER requests and force unbounded memory growth. This vulnerability is fixed in 0.17.1.","status":"published","published":"2026-04-07T14:22:19.941Z","modified":"2026-04-07T17:53:37.355Z","cvss":[{"version":"3.1","score":8.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T14:20:05.15083Z"}],"euvd":[{"id":"EUVD-2026-19650","description":"libp2p-rust is the official rust language Implementation of the libp2p networking stack. Prior to 0.17.1, the rendezvous server stores pagination cookies without bounds. An unauthenticated peer can repeatedly issue DISCOVER requests and force unbounded memory growth. This vulnerability is fixed in 0.17.1.","status":"published","published":"2026-04-07T14:22:19Z","modified":"2026-04-07T17:53:37Z","cvss":[{"version":"3.1","score":8.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"high"}],"updated_at":"2026-11-02T19:25:12.431163Z"}],"ghsa":[{"id":"GHSA-v5hw-cv9c-rpg7","title":"libp2p-rendezvous: Unbounded rendezvous DISCOVER cookies enable remote memory exhaustion","description":"### Summary\nThe rendezvous server stores pagination cookies without bounds. An unauthenticated peer can repeatedly issue `DISCOVER` requests and force unbounded memory growth.\n\n### Details\n\nPagination state is stored in:\n\n```rs\nHashMap\u003cCookie, HashSet\u003cRegistrationId\u003e\u003e\n```\n\nOn `Message::Discover`:\n\n```\nremote peer\n→ DISCOVER\n→ handle_request\n→ registrations.get(...)\n→ new cookie generated\n→ cookie inserted into Registrations::cookies\n```\n\nThere is **no upper bound or eviction policy**, so repeated DISCOVER requests grow this map indefinitely.\n\n\n### PoC\nA reproduction test and minimal harness will be provided in a private fork in a follow-up comment.\n\n### Impact\n\n**Remote state amplification leading to memory exhaustion.**\n\n\nProperties:\n\n- etwork reachable\n- no authentication required\n- low attack complexity\n- protocol-compliant traffic\n\nImpacts rendezvous nodes exposed to untrusted peers.\n---\n\n### Possible Fixes\n\n1. **Global cap + eviction**\n\nBound cookie storage (`MAX_COOKIES_TRACKED`) with FIFO/expiry aware eviction.  \nTradeoff: attacker can churn cookies and evict legitimate pagination state.\n\n2. **Stateless cookies**\n\nEncode pagination state in authenticated cookies instead of storing server-side state.  \nTradeoff: more complex implementation.\n\n3. **Rate limiting / per-peer quotas**\n\nLimit cookie creation per peer.  \nTradeoff: requires peer tracking.","status":"published","published":"2026-04-04T06:34:29Z","modified":"2026-04-07T19:59:52Z","cvss":[{"version":"3.1","score":8.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"high"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T14:39:50.076383Z"}],"nvd":[{"id":"CVE-2026-35457","description":"libp2p-rust is the official rust language Implementation of the libp2p networking stack. Prior to 0.17.1, the rendezvous server stores pagination cookies without bounds. An unauthenticated peer can repeatedly issue DISCOVER requests and force unbounded memory growth. This vulnerability is fixed in 0.17.1.","status":"published","published":"2026-04-07T15:17:43.587Z","modified":"2026-06-17T10:40:37.773Z","cvss":[{"version":"3.1","score":8.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T14:12:13.1424Z"}],"osv":[{"id":"GHSA-v5hw-cv9c-rpg7","title":"libp2p-rendezvous: Unbounded rendezvous DISCOVER cookies enable remote memory exhaustion","description":"### Summary\nThe rendezvous server stores pagination cookies without bounds. An unauthenticated peer can repeatedly issue `DISCOVER` requests and force unbounded memory growth.\n\n### Details\n\nPagination state is stored in:\n\n```rs\nHashMap\u003cCookie, HashSet\u003cRegistrationId\u003e\u003e\n```\n\nOn `Message::Discover`:\n\n```\nremote peer\n→ DISCOVER\n→ handle_request\n→ registrations.get(...)\n→ new cookie generated\n→ cookie inserted into Registrations::cookies\n```\n\nThere is **no upper bound or eviction policy**, so repeated DISCOVER requests grow this map indefinitely.\n\n\n### PoC\nA reproduction test and minimal harness will be provided in a private fork in a follow-up comment.\n\n### Impact\n\n**Remote state amplification leading to memory exhaustion.**\n\n\nProperties:\n\n- etwork reachable\n- no authentication required\n- low attack complexity\n- protocol-compliant traffic\n\nImpacts rendezvous nodes exposed to untrusted peers.\n---\n\n### Possible Fixes\n\n1. **Global cap + eviction**\n\nBound cookie storage (`MAX_COOKIES_TRACKED`) with FIFO/expiry aware eviction.  \nTradeoff: attacker can churn cookies and evict legitimate pagination state.\n\n2. **Stateless cookies**\n\nEncode pagination state in authenticated cookies instead of storing server-side state.  \nTradeoff: more complex implementation.\n\n3. **Rate limiting / per-peer quotas**\n\nLimit cookie creation per peer.  \nTradeoff: requires peer tracking.","status":"published","published":"2026-04-04T06:34:29Z","modified":"2026-04-07T20:21:43.969674Z","cvss":[{"version":"3.1","score":8.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"high"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T15:46:56.639206Z"}]}}