{"id":"RUSTSEC-2026-0340","aliases":["GHSA-3g6h-r5qx-f6hq"],"title":"Peer minimum ACK delay can panic quinn-proto when ACK_FREQUENCY transmission is enabled","summary":"Peer minimum ACK delay can panic quinn-proto when ACK_FREQUENCY transmission is enabled","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":"quinn-proto","product":"quinn-proto","ecosystem":"rust","affected":["quinn-proto >= 0.11.0, < 0.11.18"],"patched":["quinn-proto 0.11.18"],"published":"2026-09-14","updated":"2026-10-12","sourceUpdated":"2026-10-12T18:15:01.975478256Z","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/RUSTSEC-2026-0340","references":[{"url":"https://crates.io/crates/quinn-proto"},{"url":"https://rustsec.org/advisories/RUSTSEC-2026-0340.html"},{"url":"https://github.com/quinn-rs/quinn/pull/2868"}],"tags":["osv","rust"],"ingestedAt":"2026-10-13T11:45:30.200Z","slug":"RUSTSEC-2026-0340","body":"## Overview\n\nWhen sending ACK_FREQUENCY frames is enabled through\n`TransportConfig::ack_frequency_config(Some(..))`, the peer's transport parameters could cause\n`AckFrequencyState::candidate_max_ack_delay` to call `Duration::clamp` with a minimum greater\nthan its maximum, which panics.\n\nFor example, a peer advertising a `min_ack_delay` of 100,000 microseconds and a `max_ack_delay`\nof 100 milliseconds passes transport parameter validation. At a 5 ms RTT, the lower bound of the\nclamp becomes 100 ms while the upper bound is 25 ms, violating the precondition of `clamp` and\npanicking while driving the connection. Both automatically derived and explicitly configured\nmaximum ACK delays use this calculation.\n\nSending ACK_FREQUENCY frames is disabled by default, so only endpoints that opt in are affected.\n\nThe flaw was corrected in 0.11.18 by computing the delay with explicit minimum and maximum bounds\ninstead of `clamp`.\n\nThanks to [@zerox80](https://github.com/zerox80) for reporting this issue.\n\n## Affected packages\n\n- `quinn-proto >= 0.11.0, < 0.11.18`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `quinn-proto 0.11.18`","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}