{"id":"MGASA-2020-0315","aliases":[],"status":"published","title":"Updated mumble packages fix security vulnerability","description":"Updated mumble package fixes security vulnerability:\n\n\nOCB2 is known to be broken under certain conditions:\nhttps://eprint.iacr.org/2019/311\n\nTo execute the universal attacks described in the paper, an attacker\nneeds access to an encryption oracle that allows it to perform encryption\nqueries with attacker-chosen nonce. Luckily in Mumble the encryption nonce\nis a fixed counter which is far too restrictive for the universal attacks\nto be feasible against Mumble.\n\nThe basic attacks do not require an attacker-chosen nonce and as such are\nmore applicable to Mumble. They are however of limited use and do require\nan en- and a decryption oracle which Mumble seemingly does not provide at\nthe same time.\n\nTo be on the safe side, this commit implements the counter-cryptanalysis\nmeasure described in the paper in section 9 for the sender and receiver side.\nThis way if either server of client are patched, their communication is almost\ncertainly (merely lacking formal proof) not susceptible to the attacks described\nin the paper.\n\n\nFixed: Potential exploit in the OCB2 encryption (#4227)","facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"published":"2020-08-16T12:06:16Z","modified":"2026-04-16T04:25:46Z","fixes":[{"ecosystem":"Mageia:7","package":"mumble","fixed_in":["1.3.2-1.mga7"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Mageia:7","package":"mumble","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.3.2-1.mga7"}]}]}],"references":[{"url":"https://advisories.mageia.org/MGASA-2020-0315.html","tags":["advisory"]},{"url":"https://bugs.mageia.org/show_bug.cgi?id=26746","tags":["report"]},{"url":"https://github.com/mumble-voip/mumble/issues/4219","tags":["report"]},{"url":"https://github.com/mumble-voip/mumble/pull/4227","tags":["web"]}],"sources":{"osv":[{"id":"MGASA-2020-0315","title":"Updated mumble packages fix security vulnerability","description":"Updated mumble package fixes security vulnerability:\n\n\nOCB2 is known to be broken under certain conditions:\nhttps://eprint.iacr.org/2019/311\n\nTo execute the universal attacks described in the paper, an attacker\nneeds access to an encryption oracle that allows it to perform encryption\nqueries with attacker-chosen nonce. Luckily in Mumble the encryption nonce\nis a fixed counter which is far too restrictive for the universal attacks\nto be feasible against Mumble.\n\nThe basic attacks do not require an attacker-chosen nonce and as such are\nmore applicable to Mumble. They are however of limited use and do require\nan en- and a decryption oracle which Mumble seemingly does not provide at\nthe same time.\n\nTo be on the safe side, this commit implements the counter-cryptanalysis\nmeasure described in the paper in section 9 for the sender and receiver side.\nThis way if either server of client are patched, their communication is almost\ncertainly (merely lacking formal proof) not susceptible to the attacks described\nin the paper.\n\n\nFixed: Potential exploit in the OCB2 encryption (#4227)\n","status":"published","published":"2020-08-16T12:06:16Z","modified":"2026-04-16T04:25:46.900276Z","updated_at":"2026-11-02T15:49:41.151324Z"}]}}