{"id":"CVE-2026-20556","title":"In Modem, there is a possible out of bounds write due to a missing bounds check","summary":"In Modem, there is a possible out of bounds write due to a missing bounds check. This could lead to remote escalation of privilege, if a UE has connected to a rogue base station controlled by the attacker, with no additional execution pr…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","cvssSource":"adp","cwe":["CWE-787"],"vendor":"MediaTek, Inc.","product":"MediaTek chipset","affected":["mediatek_chipset MT2716","mediatek_chipset MT2735","mediatek_chipset MT2737","mediatek_chipset MT6813","mediatek_chipset MT6815","mediatek_chipset MT6833","mediatek_chipset MT6835","mediatek_chipset MT6853","mediatek_chipset MT6855","mediatek_chipset MT6858","mediatek_chipset MT6873","mediatek_chipset MT6875","mediatek_chipset MT6877","mediatek_chipset MT6878","mediatek_chipset MT6879","mediatek_chipset MT6880","mediatek_chipset MT6881","mediatek_chipset MT6883","mediatek_chipset MT6885","mediatek_chipset MT6886","mediatek_chipset MT6889","mediatek_chipset MT6890","mediatek_chipset MT6891","mediatek_chipset MT6893","mediatek_chipset MT6895","mediatek_chipset MT6896","mediatek_chipset MT6897","mediatek_chipset MT6899","mediatek_chipset MT6980","mediatek_chipset MT6982","mediatek_chipset MT6983","mediatek_chipset MT6985","mediatek_chipset MT6986","mediatek_chipset MT6988","mediatek_chipset MT6989","mediatek_chipset MT6990","mediatek_chipset MT6991","mediatek_chipset MT6993","mediatek_chipset MT8668","mediatek_chipset MT8676","mediatek_chipset MT8678","mediatek_chipset MT8755","mediatek_chipset MT8771","mediatek_chipset MT8775","mediatek_chipset MT8791","mediatek_chipset MT8791T","mediatek_chipset MT8792","mediatek_chipset MT8793","mediatek_chipset MT8796","mediatek_chipset MT8797"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-11-02T00:00:00+00:00"},"published":"2026-11-02","updated":"2026-11-04","sourceUpdated":"2026-11-04T04:55:34.353Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-20556","references":[{"url":"https://www.mediatek.com/product-security-bulletin/November-2026"}],"tags":["cve.org"],"epss":0.00232,"epssPercentile":0.14221,"ingestedAt":"2026-11-05T20:33:06.667Z","slug":"CVE-2026-20556","body":"## Overview\n\nIn Modem, there is a possible out of bounds write due to a missing bounds check. This could lead to remote escalation of privilege, if a UE has connected to a rogue base station controlled by the attacker, with no additional execution privileges needed. User interaction is not needed for exploitation. Patch ID: MOLY01876662; Issue ID: MSV-9833.\n\n## Affected\n\n- `mediatek_chipset MT2716`\n- `mediatek_chipset MT2735`\n- `mediatek_chipset MT2737`\n- `mediatek_chipset MT6813`\n- `mediatek_chipset MT6815`\n- `mediatek_chipset MT6833`\n- `mediatek_chipset MT6835`\n- `mediatek_chipset MT6853`\n- `mediatek_chipset MT6855`\n- `mediatek_chipset MT6858`\n- `mediatek_chipset MT6873`\n- `mediatek_chipset MT6875`\n- `mediatek_chipset MT6877`\n- `mediatek_chipset MT6878`\n- `mediatek_chipset MT6879`\n- `mediatek_chipset MT6880`\n- `mediatek_chipset MT6881`\n- `mediatek_chipset MT6883`\n- `mediatek_chipset MT6885`\n- `mediatek_chipset MT6886`\n- `mediatek_chipset MT6889`\n- `mediatek_chipset MT6890`\n- `mediatek_chipset MT6891`\n- `mediatek_chipset MT6893`\n- `mediatek_chipset MT6895`\n- `mediatek_chipset MT6896`\n- `mediatek_chipset MT6897`\n- `mediatek_chipset MT6899`\n- `mediatek_chipset MT6980`\n- `mediatek_chipset MT6982`\n- `mediatek_chipset MT6983`\n- `mediatek_chipset MT6985`\n- `mediatek_chipset MT6986`\n- `mediatek_chipset MT6988`\n- `mediatek_chipset MT6989`\n- `mediatek_chipset MT6990`\n- `mediatek_chipset MT6991`\n- `mediatek_chipset MT6993`\n- `mediatek_chipset MT8668`\n- `mediatek_chipset MT8676`\n- `mediatek_chipset MT8678`\n- `mediatek_chipset MT8755`\n- `mediatek_chipset MT8771`\n- `mediatek_chipset MT8775`\n- `mediatek_chipset MT8791`\n- `mediatek_chipset MT8791T`\n- `mediatek_chipset MT8792`\n- `mediatek_chipset MT8793`\n- `mediatek_chipset MT8796`\n- `mediatek_chipset MT8797`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}