{"id":"CVE-2018-1000656","aliases":["DEBIAN-CVE-2018-1000656","DLA-1892-1","EUVD-2018-0075","GHSA-562c-5r94-xh97","PYSEC-2018-66","RHSA-2020:0870","SUSE-SU-2019:0657-1","UBUNTU-CVE-2018-1000656","USN-4378-1","openSUSE-SU-2019:1112-1"],"status":"published","title":"Flask is vulnerable to Denial of Service via incorrect encoding of JSON data","description":"The Pallets Project flask version Before 0.12.3 contains a CWE-20: Improper Input Validation vulnerability in flask that can result in Large amount of memory usage possibly leading to denial of service. This attack appear to be exploitable via Attacker provides JSON data in incorrect encoding. This vulnerability appears to have been fixed in 0.12.3. 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Pallets Project flask version Before 0.12.3 contains a CWE-20: Improper Input Validation vulnerability in flask that can result in Large amount of memory usage possibly leading to denial of service. This attack appear to be exploitable via Attacker provides JSON data in incorrect encoding. This vulnerability appears to have been fixed in 0.12.3. NOTE: this may overlap CVE-2019-1010083.","status":"published","published":"2018-08-20T19:00:00Z","modified":"2024-08-05T12:40:47.801Z","updated_at":"2026-11-02T14:35:10.685174Z"}],"euvd":[{"id":"EUVD-2018-0075","description":"The Pallets Project flask version Before 0.12.3 contains a CWE-20: Improper Input Validation vulnerability in flask that can result in Large amount of memory usage possibly leading to denial of service. This attack appear to be exploitable via Attacker provides JSON data in incorrect encoding. This vulnerability appears to have been fixed in 0.12.3. NOTE: this may overlap CVE-2019-1010083.","status":"published","published":"2018-08-20T19:00:00Z","modified":"2024-08-05T12:40:47Z","updated_at":"2026-11-03T02:39:26.268404Z"}],"ghsa":[{"id":"GHSA-562c-5r94-xh97","title":"Flask is vulnerable to Denial of Service via incorrect encoding of JSON data","description":"The Pallets Project flask version Before 0.12.3 contains a CWE-20: Improper Input Validation vulnerability in flask that can result in Large amount of memory usage possibly leading to denial of service. This attack appear to be exploitable via Attacker provides JSON data in incorrect encoding. 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NOTE: this may overlap CVE-2019-1010083.","status":"published","published":"2018-08-20T19:31:45.34Z","modified":"2026-06-17T01:33:02.153Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:N/I:N/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T14:04:36.842579Z"}],"osv":[{"id":"CVE-2018-1000656","description":"The Pallets Project flask version Before 0.12.3 contains a CWE-20: Improper Input Validation vulnerability in flask that can result in Large amount of memory usage possibly leading to denial of service. This attack appear to be exploitable via Attacker provides JSON data in incorrect encoding. This vulnerability appears to have been fixed in 0.12.3. 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This attack appear to be exploitable via Attacker provides JSON data in incorrect encoding. This vulnerability appears to have been fixed in 0.12.3. NOTE: this may overlap CVE-2019-1010083.","status":"published","published":"2018-08-20T19:31:00Z","modified":"2026-02-04T03:29:41.428932Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T15:54:16.544091Z"},{"id":"DLA-1892-1","title":"flask - security update","status":"published","published":"2019-08-20T00:00:00Z","modified":"2026-03-09T01:20:22.610162Z","updated_at":"2026-11-02T15:46:10.227108Z"},{"id":"openSUSE-SU-2019:1112-1","title":"Security update for python-Flask","description":"This update for python-Flask to version 0.12.4 fixes the following issues:\n\nSecurity issue fixed:\n\n- CVE-2018-1000656: Fixed an improper input validation vulnerability in flask\n  that can result in Large amount of memory usage possibly leading to denial of\n  service. (bsc#1106279)\n\nThis update was imported from the SUSE:SLE-15:Update update project.","status":"published","published":"2019-04-02T11:03:44Z","modified":"2026-02-04T04:04:40.998441Z","updated_at":"2026-11-02T16:58:30.784344Z"},{"id":"PYSEC-2018-66","description":"The Pallets Project flask version Before 0.12.3 contains a CWE-20: Improper Input Validation vulnerability in flask that can result in Large amount of memory usage possibly leading to denial of service. This attack appear to be exploitable via Attacker provides JSON data in incorrect encoding. This vulnerability appears to have been fixed in 0.12.3. NOTE: this may overlap CVE-2019-1010083.","status":"published","published":"2018-08-20T19:31:00Z","modified":"2023-11-08T03:59:39.887416Z","updated_at":"2026-11-02T15:52:52.192131Z"},{"id":"SUSE-SU-2019:0657-1","title":"Security update for python-Flask","description":"This update for python-Flask to version 0.12.4 fixes the following issues:\n\nSecurity issue fixed:\n\n- CVE-2018-1000656: Fixed an improper input validation vulnerability in flask\n  that can result in Large amount of memory usage possibly leading to denial of\n  service. (bsc#1106279)\n","status":"published","published":"2019-03-20T11:49:45Z","modified":"2026-02-04T03:12:28.423758Z","updated_at":"2026-11-02T15:53:45.926331Z"},{"id":"USN-4378-1","title":"flask vulnerability","description":"It was discovered that Flask incorrectly handled certain inputs.\nAn attacker could possibly use this issue to cause a denial of service.\n","status":"published","published":"2020-06-01T15:28:34Z","modified":"2026-06-29T13:48:00.486457348Z","updated_at":"2026-11-02T16:58:14.547547Z"}]}}