{"id":"CVE-2026-33040","aliases":["EUVD-2026-13581","GHSA-gc42-3jg7-rxr2","UBUNTU-CVE-2026-33040"],"status":"published","title":"libp2p-rust: Gossipsub PRUNE.backoff Duration Overflow","description":"libp2p-rust is the official rust language Implementation of the libp2p networking stack. In versions prior to 0.49.3, the Gossipsub implementation accepts attacker-controlled PRUNE backoff values and may perform unchecked time arithmetic when storing backoff state. A specially crafted PRUNE control message with an extremely large backoff (e.g. u64::MAX) can lead to Duration/Instant overflow during backoff update logic, triggering a panic in the networking state machine. This is remotely reachable over a normal libp2p connection and does not require authentication. Any application exposing a libp2p Gossipsub listener and using the affected backoff-handling path can be crashed by a network attacker that can reach the service port. The attack can be repeated by reconnecting and replaying the crafted control message. This issue has been fixed in version 0.49.3.","severity":{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00602,"percentile":0.49243,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-190"],"published":"2026-03-18T19:54:12Z","modified":"2026-10-17T12:59:59Z","fixes":[{"ecosystem":"crates.io","package":"libp2p-gossipsub","fixed_in":["0.49.3"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"crates.io","package":"libp2p-gossipsub","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.49.3"}]}]},{"source":"osv","ecosystem":"crates.io","package":"libp2p-gossipsub","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"0.49.3"}]}]},{"source":"osv","ecosystem":"Ubuntu:25.10","package":"rust-libp2p-identity","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.2.10+20250205+ds-1"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"rust-libp2p-identity","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.2.13+ds-1"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"rust-libp2p-identity","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.2.10+20250205+ds-1","0.2.12+20250805+ds-2","0.2.13+ds-1"]}],"products":[{"vendor":"libp2p","product":"rust-libp2p"},{"vendor":"protocol","product":"libp2p-gossipsub"}],"references":[{"url":"https://github.com/libp2p/rust-libp2p/security/advisories/GHSA-gc42-3jg7-rxr2","tags":["x_refsource_CONFIRM","Vendor Advisory","web","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-33040","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-gc42-3jg7-rxr2"},{"url":"https://github.com/libp2p/rust-libp2p","tags":["package"]},{"url":"https://ubuntu.com/security/CVE-2026-33040","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-33040","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-33040","title":"libp2p-rust: Gossipsub PRUNE.backoff Duration Overflow","description":"libp2p-rust is the official rust language Implementation of the libp2p networking stack. In versions prior to 0.49.3, the Gossipsub implementation accepts attacker-controlled PRUNE backoff values and may perform unchecked time arithmetic when storing backoff state. A specially crafted PRUNE control message with an extremely large backoff (e.g. u64::MAX) can lead to Duration/Instant overflow during backoff update logic, triggering a panic in the networking state machine. This is remotely reachable over a normal libp2p connection and does not require authentication. Any application exposing a libp2p Gossipsub listener and using the affected backoff-handling path can be crashed by a network attacker that can reach the service port. The attack can be repeated by reconnecting and replaying the crafted control message. This issue has been fixed in version 0.49.3.","status":"published","published":"2026-03-20T05:46:42.276Z","modified":"2026-03-20T15:41:03.864Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna"}],"cwes":["CWE-190"],"updated_at":"2026-11-02T14:20:07.609948Z"}],"euvd":[{"id":"EUVD-2026-13581","description":"libp2p-rust is the official rust language Implementation of the libp2p networking stack. In versions prior to 0.49.3, the Gossipsub implementation accepts attacker-controlled PRUNE backoff values and may perform unchecked time arithmetic when storing backoff state. A specially crafted PRUNE control message with an extremely large backoff (e.g. u64::MAX) can lead to Duration/Instant overflow during backoff update logic, triggering a panic in the networking state machine. This is remotely reachable over a normal libp2p connection and does not require authentication. Any application exposing a libp2p Gossipsub listener and using the affected backoff-handling path can be crashed by a network attacker that can reach the service port. The attack can be repeated by reconnecting and replaying the crafted control message. This issue has been fixed in version 0.49.3.","status":"published","published":"2026-03-20T05:46:42Z","modified":"2026-03-20T15:41:03Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high"}],"updated_at":"2026-11-02T19:25:32.430758Z"}],"ghsa":[{"id":"GHSA-gc42-3jg7-rxr2","title":"Gossipsub PRUNE.backoff Duration Overflow","description":"### Summary\nThe Rust libp2p Gossipsub implementation accepts attacker-controlled PRUNE backoff values and may perform unchecked time arithmetic when storing backoff state.\nA specially crafted PRUNE control message with an extremely large backoff (e.g. u64::MAX) can lead to Duration/Instant overflow during backoff update logic, triggering a panic in the networking state machine. This is remotely reachable over a normal libp2p connection and does not require authentication.\n\n### Attack Scenario\nAn attacker that can establish a libp2p Gossipsub session with a target node can crash the target by sending a single crafted PRUNE control message:\n1. Establish a standard libp2p transport session and negotiate a stream multiplexer.\n2. Open a Gossipsub stream and negotiate the meshsub protocol.\n3. Send one protobuf RPC containing ControlPrune with a very large backoff value (e.g. 18446744073709551615 / u64::MAX).\nWhen processed, the oversized backoff can reach time-update logic that adds Duration::from_secs(backoff) to Instant::now(), causing overflow and panic.\n\n### Impact\nRemote unauthenticated denial of service.\nAny application exposing a libp2p Gossipsub listener and using the affected backoff-handling path can be crashed by a network attacker that can reach the service port. The attack can be repeated by reconnecting and replaying the crafted control message.\n### Patches\nUsers should upgrade to a release that hardens Gossipsub backoff handling.\n\nThis vulnerability was originally submitted by @revofusion to the Ethereum Foundation bug bounty program","status":"published","published":"2026-03-18T19:54:12Z","modified":"2026-03-20T21:23:16Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high"}],"cwes":["CWE-190"],"updated_at":"2026-11-02T14:39:39.567266Z"}],"nvd":[{"id":"CVE-2026-33040","description":"libp2p-rust is the official rust language Implementation of the libp2p networking stack. In versions prior to 0.49.3, the Gossipsub implementation accepts attacker-controlled PRUNE backoff values and may perform unchecked time arithmetic when storing backoff state. A specially crafted PRUNE control message with an extremely large backoff (e.g. u64::MAX) can lead to Duration/Instant overflow during backoff update logic, triggering a panic in the networking state machine. This is remotely reachable over a normal libp2p connection and does not require authentication. Any application exposing a libp2p Gossipsub listener and using the affected backoff-handling path can be crashed by a network attacker that can reach the service port. The attack can be repeated by reconnecting and replaying the crafted control message. This issue has been fixed in version 0.49.3.","status":"published","published":"2026-03-20T06:16:12.33Z","modified":"2026-06-17T10:36:51.167Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high","assessor":"secondary"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary"}],"cwes":["CWE-190"],"updated_at":"2026-11-02T14:12:10.126802Z"}],"osv":[{"id":"GHSA-gc42-3jg7-rxr2","title":"Gossipsub PRUNE.backoff Duration Overflow","description":"### Summary\nThe Rust libp2p Gossipsub implementation accepts attacker-controlled PRUNE backoff values and may perform unchecked time arithmetic when storing backoff state.\nA specially crafted PRUNE control message with an extremely large backoff (e.g. u64::MAX) can lead to Duration/Instant overflow during backoff update logic, triggering a panic in the networking state machine. This is remotely reachable over a normal libp2p connection and does not require authentication.\n\n### Attack Scenario\nAn attacker that can establish a libp2p Gossipsub session with a target node can crash the target by sending a single crafted PRUNE control message:\n1. Establish a standard libp2p transport session and negotiate a stream multiplexer.\n2. Open a Gossipsub stream and negotiate the meshsub protocol.\n3. Send one protobuf RPC containing ControlPrune with a very large backoff value (e.g. 18446744073709551615 / u64::MAX).\nWhen processed, the oversized backoff can reach time-update logic that adds Duration::from_secs(backoff) to Instant::now(), causing overflow and panic.\n\n### Impact\nRemote unauthenticated denial of service.\nAny application exposing a libp2p Gossipsub listener and using the affected backoff-handling path can be crashed by a network attacker that can reach the service port. The attack can be repeated by reconnecting and replaying the crafted control message.\n### Patches\nUsers should upgrade to a release that hardens Gossipsub backoff handling.\n\nThis vulnerability was originally submitted by @revofusion to the Ethereum Foundation bug bounty program","status":"published","published":"2026-03-18T19:54:12Z","modified":"2026-03-20T21:34:48.742824Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high"}],"cwes":["CWE-190"],"updated_at":"2026-11-02T15:46:47.472172Z"},{"id":"UBUNTU-CVE-2026-33040","description":"libp2p-rust is the official rust language Implementation of the libp2p networking stack. In versions prior to 0.49.3, the Gossipsub implementation accepts attacker-controlled PRUNE backoff values and may perform unchecked time arithmetic when storing backoff state. A specially crafted PRUNE control message with an extremely large backoff (e.g. u64::MAX) can lead to Duration/Instant overflow during backoff update logic, triggering a panic in the networking state machine. This is remotely reachable over a normal libp2p connection and does not require authentication. Any application exposing a libp2p Gossipsub listener and using the affected backoff-handling path can be crashed by a network attacker that can reach the service port. The attack can be repeated by reconnecting and replaying the crafted control message. This issue has been fixed in version 0.49.3.","status":"published","published":"2026-03-20T06:16:00Z","modified":"2026-10-17T12:59:59.413716895Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T16:56:16.036833Z"}]}}