MediaTek Modem OOB and Memory Corruption Flaws

An out-of-bounds write in MediaTek modem (baseband) firmware allows an attacker operating a rogue base station to escalate privileges on a wide range of MediaTek chipsets (e.g., MT6853, MT6980, MT6991, MT8798, MT6895) once the victim's device connects to that base station; no authentication is required, but exploitation is high-complexity and requires user interaction per the assessed vector. No public exploit code or confirmed active exploitation has been identified at time of analysis, and the risk is bounded by the need for RF proximity to a malicious base station rather than being a mass-exploitable remote flaw.

Memory corruption in the MediaTek cellular modem baseband (an out-of-bounds write from a missing bounds check) allows an attacker who operates a rogue base station within radio range to escalate privileges on the target device without authentication and without any user interaction. Exploitation is not reachable over the internet: the CVSS vector AV:A/AC:H/PR:N/UI:N with C:H/I:H/A:H reflects that the attacker must be in adjacent radio proximity and must successfully induce the victim's UE to attach to the malicious base station, and CISA's SSVC assessment records Exploitation: none and Automatable: no, so this is a conditionally gated baseband flaw rather than a mass-exploitation emergency. No public exploit code has been identified at time of analysis; MediaTek has released a fix under Patch ID MOLY01778988 (Issue ID MSV-8897) in its October 2026 product security bulletin.

An out-of-bounds write in MediaTek modem firmware (CWE-787) allows a nearby attacker operating a rogue base station to escalate privileges on affected devices once the user equipment attaches to the attacker-controlled cell. The flaw has a CVSS 3.1 base score of 7.5 (AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H) and affects dozens of MediaTek chipsets, including MT6833, MT6877, MT6983, MT6985, and MT6989, when they run unpatched modem firmware. No public exploit code has been identified at time of analysis, CISA's SSVC assessment records no observed exploitation and marks the issue as not automatable, and MediaTek has published a fix under Patch ID MOLY01778993 in its October 2026 product security bulletin.

Local information disclosure in MediaTek Modem firmware affects devices built on more than 80 MediaTek chipset models, including MT6983, MT6895, MT6989, and MT6768, when running unpatched modem firmware. A local app with ordinary low privileges (PR:L) can access sensitive modem debug information without user interaction, yielding high confidentiality impact but no code execution or integrity/availability loss; CVSS is 5.5 (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N). No public exploit code has been identified at time of analysis, and there is no CISA KEV entry indicating confirmed active exploitation, but MediaTek patch MOLY01645293 and the October 2026 product security bulletin address the flaw.

Remote denial of service against MediaTek modem (baseband) firmware affects more than 80 chipsets - including MT6765, MT6785, MT6833, MT6883, MT6985, MT6991 and MT8798 - where a missing bounds check during cellular message parsing produces an out-of-bounds read (CWE-126) that can crash the baseband. An attacker who operates a rogue base station and gets a victim UE to attach can trigger the fault with no authentication (PR:N) and no user interaction (UI:N), though the adjacent-network position and specialized radio hardware required drive the high attack complexity (AC:H) and the CVSS 3.1 score of 5.3, with impact limited to availability. Neither our independent assessment nor CISA's SSVC framework records known exploitation (Exploitation: none, Automatable: no), so no public exploit is identified at time of analysis.

Denial of service in MediaTek's cellular modem firmware can crash the baseband on a broad set of MediaTek chipsets - including MT6991, MT6988, MT6897, MT8755, MT6835, MT8792 and others - causing the device to drop connectivity or reset. Exploitation is unauthenticated (PR:N, UI:N) but requires the attacker to operate a rogue, attacker-controlled base station and to get the target user equipment to attach to it over the radio interface, which is why attack complexity is rated high (AV:A/AC:H) and impact is limited to availability (A:H; no confidentiality or integrity effect). MediaTek publishes fix identifiers MOLY01870473 / MOLY00814393 (issue MSV-9041) in its October 2026 product security bulletin; no public exploit code and no confirmed active exploitation have been identified at time of analysis, and CISA's SSVC assessment rates exploitation as 'none' with partial technical impact, keeping real-world priority moderate-to-low despite the large number of affected chipsets.

Out-of-bounds read in MediaTek modem firmware (CWE-126) allows an attacker operating a rogue base station to trigger a memory over-read in the modem stack of any UE that connects to it, resulting in a remote denial of service (availability only; no data exposure or code execution). The issue affects a very wide set of MediaTek chipsets (MT6989, MT6990, MT6983, MT6768, MT6765 and dozens more) enumerated in MediaTek's October 2026 product security bulletin. No authentication or user interaction is required (CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H, base 5.3), but practical exploitation demands radio proximity, rogue base-station infrastructure, and the ability to coerce device attachment - CISA SSVC rates exploitation 'none' and automatable 'no', and no public exploit code or confirmed active exploitation was identified at time of analysis, making this a genuine but moderate-priority issue rather than a critical one.

Modem denial of service in MediaTek baseband firmware allows an attacker operating a rogue base station within radio range to crash or reset a victim handset's modem through an out-of-bounds read (CWE-125) caused by an incorrect bounds check on attacker-influenced over-the-air data. The attacker must first get the target UE to camp on the malicious cell (CVSS 3.1 AV:A/AC:H), after which no privileges and no user interaction are required, and the only impact is loss of availability of the modem (A:H, C:N/I:N), yielding a 5.3 base score. There is no public exploit identified at time of analysis, CISA's SSVC assessment records Exploitation=none and Automatable=no, and applicability is limited to devices built on the enumerated MediaTek chipset models with vulnerable modem firmware, so this is a genuine but bounded, proximity-dependent availability risk rather than a mass-exploitation emergency.

A missing permission check in MediaTek modem firmware permits an out-of-bounds read that can crash the baseband, producing a remote denial of service on affected handsets. The attack is unauthenticated (CVSS PR:N) and requires no user interaction (UI:N), but it only succeeds if the victim UE is already camped on a rogue base station the attacker controls, which is why the vector is scored AV:A/AC:H and the issue is assessed as moderate severity and low real-world priority. No public exploit code has been identified at the time of analysis, and impact is limited to availability of the modem - no confidentiality or integrity loss, and no code execution. MediaTek has issued a fix under Patch ID MOLY01774038 / Issue ID MSV-8911.

Denial of service in MediaTek cellular modem firmware lets an attacker running a rogue base station crash the modem of an attached device by delivering a malformed message that triggers a missing bounds check, severing cellular connectivity until the modem restarts. The flaw is availability-only (CVSS 5.3, AV:A/AC:H/PR:N/UI:N/C:N/I:N/A:H) and is gated by radio proximity plus the victim UE actually attaching to the attacker-controlled cell, so it is not reachable over the internet and carries no confidentiality or integrity impact. No public exploit code and no confirmed active exploitation were identified at time of analysis, and MediaTek has shipped fixes (patch IDs MOLY01864925 / MOLY01210562) covering more than 50 chipsets across the October 2026 product security bulletin.

Denial of service against the cellular modem firmware shipped in a very broad range of MediaTek chipsets (MT6739 through MT6993/MT8893 families) arises from an out-of-bounds read caused by a missing permission check. The precondition is that the victim user equipment has already attached to a rogue base station under the attacker's control, meaning the adversary must operate radio infrastructure within range and successfully induce attachment (downgrade or stronger-signal lure) - hence the AV:A/AC:H scoring and the LOW real-world priority despite the enormous chipset footprint. Once attached, exploiting the flaw requires no authentication (PR:N) and no user interaction (UI:N), but the outcome is availability-only (A:H, with no confidentiality or integrity impact); there is confirmed no active exploitation (CISA KEV absent), no public exploit code identified at time of analysis, and no EPSS signal was provided in the source data.