# CVE-2026-20484: MediaTek TFA information disclosure due to missing permission check Source: https://junglewise.ai/threats/cve-2026-20484-mediatek-tfa-information-disclosure-due-to-missing-permission Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats Published: 2026-08-03. Updated: 2026-09-25 License: CC BY 4.0 with a link back CVE-2026-20484 · Severity: medium · CVSS 4.4 · Published 2026-08-03 MediaTek's TFA (Trusted Firmware-A) component is a critical low-level software that manages system security and access control. A flaw in this component fails to properly verify permissions before disclosing sensitive system information, allowing an attacker with System privilege to read confidential data. Although exploitation requires prior privilege escalation, the exposure of system information could enable further attacks or reveal sensitive operational details. Technologies: [MediaTek Mt6739](https://junglewise.ai/threats/technologies/mt6739), [MediaTek Mt6739 Firmware](https://junglewise.ai/threats/technologies/mt6739-firmware), [MediaTek Mt6761](https://junglewise.ai/threats/technologies/mt6761), [MediaTek Mt6761 Firmware](https://junglewise.ai/threats/technologies/mt6761-firmware), [MediaTek Mt6765](https://junglewise.ai/threats/technologies/mt6765), [MediaTek Mt6765 Firmware](https://junglewise.ai/threats/technologies/mt6765-firmware), [MediaTek Mt6768](https://junglewise.ai/threats/technologies/mt6768), [MediaTek Mt6768 Firmware](https://junglewise.ai/threats/technologies/mt6768-firmware), [MediaTek Mt6781](https://junglewise.ai/threats/technologies/mt6781), [MediaTek Mt6781 Firmware](https://junglewise.ai/threats/technologies/mt6781-firmware), [MediaTek Mt6789](https://junglewise.ai/threats/technologies/mt6789), [MediaTek Mt6789 Firmware](https://junglewise.ai/threats/technologies/mt6789-firmware), [MediaTek MT6833](https://junglewise.ai/threats/technologies/mt6833), [MediaTek Mt6833 Firmware](https://junglewise.ai/threats/technologies/mt6833-firmware), [MediaTek Mt6835](https://junglewise.ai/threats/technologies/mt6835), [MediaTek Mt6835 Firmware](https://junglewise.ai/threats/technologies/mt6835-firmware), [MediaTek Mt6853](https://junglewise.ai/threats/technologies/mt6853), [MediaTek Mt6853 Firmware](https://junglewise.ai/threats/technologies/mt6853-firmware), [MediaTek Mt6855](https://junglewise.ai/threats/technologies/mt6855), [MediaTek Mt6855 Firmware](https://junglewise.ai/threats/technologies/mt6855-firmware), [MediaTek Mt6877](https://junglewise.ai/threats/technologies/mt6877), [MediaTek Mt6877 Firmware](https://junglewise.ai/threats/technologies/mt6877-firmware), [MediaTek Mt6878](https://junglewise.ai/threats/technologies/mt6878), [MediaTek Mt6878 Firmware](https://junglewise.ai/threats/technologies/mt6878-firmware), [MediaTek Mt6879](https://junglewise.ai/threats/technologies/mt6879), [MediaTek Mt6879 Firmware](https://junglewise.ai/threats/technologies/mt6879-firmware), [MediaTek Mt6883](https://junglewise.ai/threats/technologies/mt6883), [MediaTek Mt6883 Firmware](https://junglewise.ai/threats/technologies/mt6883-firmware), [MediaTek Mt6885](https://junglewise.ai/threats/technologies/mt6885), [MediaTek Mt6885 Firmware](https://junglewise.ai/threats/technologies/mt6885-firmware), [MediaTek Mt6886](https://junglewise.ai/threats/technologies/mt6886), [MediaTek Mt6886 Firmware](https://junglewise.ai/threats/technologies/mt6886-firmware), [MediaTek Mt6889](https://junglewise.ai/threats/technologies/mt6889), [MediaTek Mt6889 Firmware](https://junglewise.ai/threats/technologies/mt6889-firmware), [MediaTek Mt6893](https://junglewise.ai/threats/technologies/mt6893), [MediaTek Mt6893 Firmware](https://junglewise.ai/threats/technologies/mt6893-firmware), [MediaTek Mt6895](https://junglewise.ai/threats/technologies/mt6895), [MediaTek Mt6895 Firmware](https://junglewise.ai/threats/technologies/mt6895-firmware), [MediaTek Mt6897](https://junglewise.ai/threats/technologies/mt6897), [MediaTek Mt6897 Firmware](https://junglewise.ai/threats/technologies/mt6897-firmware), [MediaTek Mt6899](https://junglewise.ai/threats/technologies/mt6899), [MediaTek Mt6899 Firmware](https://junglewise.ai/threats/technologies/mt6899-firmware), [MediaTek Mt6983](https://junglewise.ai/threats/technologies/mt6983), [MediaTek Mt6983 Firmware](https://junglewise.ai/threats/technologies/mt6983-firmware), [MediaTek Mt6985](https://junglewise.ai/threats/technologies/mt6985), [MediaTek Mt6985 Firmware](https://junglewise.ai/threats/technologies/mt6985-firmware), [MediaTek MT6988](https://junglewise.ai/threats/technologies/mt6988), [MediaTek Mt6988 Firmware](https://junglewise.ai/threats/technologies/mt6988-firmware), [MediaTek Mt6989](https://junglewise.ai/threats/technologies/mt6989), [MediaTek Mt6989 Firmware](https://junglewise.ai/threats/technologies/mt6989-firmware), [MediaTek Mt6991](https://junglewise.ai/threats/technologies/mt6991), [MediaTek Mt6991 Firmware](https://junglewise.ai/threats/technologies/mt6991-firmware), [MediaTek MT6993](https://junglewise.ai/threats/technologies/mt6993), [MediaTek Mt6993 Firmware](https://junglewise.ai/threats/technologies/mt6993-firmware), [MediaTek Mt8171](https://junglewise.ai/threats/technologies/mt8171), [MediaTek Mt8171 Firmware](https://junglewise.ai/threats/technologies/mt8171-firmware), [MediaTek Mt8188](https://junglewise.ai/threats/technologies/mt8188), [MediaTek Mt8188 Firmware](https://junglewise.ai/threats/technologies/mt8188-firmware), [MediaTek Mt8189](https://junglewise.ai/threats/technologies/mt8189), [MediaTek Mt8189 Firmware](https://junglewise.ai/threats/technologies/mt8189-firmware), [MediaTek Mt8390](https://junglewise.ai/threats/technologies/mt8390), [MediaTek Mt8390 Firmware](https://junglewise.ai/threats/technologies/mt8390-firmware), [MediaTek Mt8391](https://junglewise.ai/threats/technologies/mt8391), [MediaTek Mt8391 Firmware](https://junglewise.ai/threats/technologies/mt8391-firmware), [MediaTek Mt8668](https://junglewise.ai/threats/technologies/mt8668), [MediaTek Mt8668 Firmware](https://junglewise.ai/threats/technologies/mt8668-firmware), [MediaTek MT8676](https://junglewise.ai/threats/technologies/mt8676), [MediaTek Mt8676 Firmware](https://junglewise.ai/threats/technologies/mt8676-firmware), [MediaTek MT8678](https://junglewise.ai/threats/technologies/mt8678), [MediaTek Mt8678 Firmware](https://junglewise.ai/threats/technologies/mt8678-firmware), [MediaTek MT8696](https://junglewise.ai/threats/technologies/mt8696), [MediaTek Mt8696 Firmware](https://junglewise.ai/threats/technologies/mt8696-firmware), [MediaTek MT8792](https://junglewise.ai/threats/technologies/mt8792), [MediaTek Mt8792 Firmware](https://junglewise.ai/threats/technologies/mt8792-firmware), [MediaTek Mt8793](https://junglewise.ai/threats/technologies/mt8793), [MediaTek Mt8793 Firmware](https://junglewise.ai/threats/technologies/mt8793-firmware), [MediaTek Mt8799](https://junglewise.ai/threats/technologies/mt8799), [MediaTek Mt8799 Firmware](https://junglewise.ai/threats/technologies/mt8799-firmware). Vendors: [MediaTek](https://junglewise.ai/threats/vendors/mediatek). ## Quick answers **Is CVE-2026-20484 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-20484 being exploited in the wild. **How severe is CVE-2026-20484?** Medium severity, with a CVSS score of 4.4, published 3 August 2026. **Which products and versions are affected?** MediaTek TFA (Trusted Firmware-A). **Is there a fix for CVE-2026-20484?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it. **How is CVE-2026-20484 attacked?** It is attacked with local access, in device firmware. **Am I affected by CVE-2026-20484?** Check whether you run MediaTek Mt6739, MediaTek Mt6739 Firmware, MediaTek Mt6761 or one of the others listed. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you. ## Technical details This vulnerability is classified as an information disclosure flaw resulting from a missing permission check in the TFA subcomponent. An attacker who has already obtained System privilege can bypass access controls and retrieve restricted system information without requiring user interaction. The missing authorization validation allows unauthorized exposure of sensitive data that should be protected. The vulnerability is tracked by MediaTek as Issue ID MSV-8004 and has been assigned Patch ID ALPS11053160. No active exploitation in the wild has been reported as of the advisory date. ## Affected products - MediaTek TFA (Trusted Firmware-A) ## Timeline - 2026-08-03: disclosed ## References - [https://www.mediatek.com/product-security-bulletin/August-2026](https://www.mediatek.com/product-security-bulletin/August-2026) ## Related threats - [MediaTek vdec out-of-bounds write in type confusion](https://junglewise.ai/threats/cve-2026-20579-in-vdec-there-is-a-possible-out-of-bounds-write-due-to-type) - [MediaTek out of bounds write in modem](https://junglewise.ai/threats/cve-2026-20544-in-meta-there-is-a-possible-out-of-bounds-write-due-to-a-missing) - [MediaTek Modem information disclosure due to logic error](https://junglewise.ai/threats/cve-2026-20543-in-modem-there-is-a-possible-information-disclosure-due-to-a) - [MediaTek Modem out-of-bounds read due to missing permission check](https://junglewise.ai/threats/cve-2026-20538-in-modem-there-is-a-possible-out-of-bounds-read-due-to-a-missing) - [MediaTek Modem out of bounds read](https://junglewise.ai/threats/cve-2026-20534-in-modem-there-is-a-possible-out-of-bounds-read-due-to-an)