TI-2026-83717 Aliases CVE-2026-20576 GHSA-4qcx-99jw-5fpf

Out-of-bounds write in MediaTek afe enables local privilege escalation

LOW 30CWE-191Published 2026-11-02 · Updated 2026-11-03

Key facts

Attack vector: Local
Privileges required: High
User interaction: None
Attack complexity: Low
Impact type: Code execution
Confidentiality · integrity · availability: High · High · High
Fix status: No fix listed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-191 and the CVSS impact.

Summary

MediaTek chipsets MT6789, MT6835, MT6855, MT6858, MT6877 and other models are affected in the afe component. A missing bounds check leads to an integer underflow (CWE-191) that causes an out-of-bounds write. A local attacker who already holds System privilege can escalate privileges, and no user interaction is needed.

Written with Claude Haiku 5.5 from the sources below · 2026-11-02

Description from the CNA

In afe, there is a possible out of bounds write due to a missing bounds check. This could lead to local escalation of privilege if a malicious actor has already obtained the System privilege. User interaction is not needed for exploitation. Patch ID: ALPS11431385; Issue ID: MSV-9920.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00109 1st percentileScored 2026-11-07

Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
MediaTek	MediaTek chipset	MT6789; MT6835; MT6855; MT6858; MT6877; MT6885; MT6886; MT6895; MT6897; MT6985; MT6988; MT6989; MT6991; MT6993	—	No fix listed	CNA

MediaTek chipset VendorMediaTek Affected MT6789; MT6835; MT6855; MT6858; MT6877; MT6885; MT6886; MT6895; MT6897; MT6985; MT6988; MT6989; MT6991; MT6993 Fixed in — No fix listed CNA

Remediation

The sources list no fixed version for MediaTek chipset.

Written with Claude Haiku 5.5 from the sources below · 2026-11-02

Timeline

2026-11-02 Threatist record created from CVE-2026-20576
2026-11-02 Alias added: GHSA-4qcx-99jw-5fpf
2026-11-02 CVSS score added · CISA ADP
2026-11-02 CISA SSVC decision points changed
2026-11-03 CISA SSVC decision points changed

References

Other 1

https://www.mediatek.com/product-security-bulletin/November-2026

TI-2020-00067 Out-of-bounds write in Android KEVCVSS 3.1HIGH 7.8
TI-2024-13053 Improper input validation in MediaTek MT6890, MT7915, MT7916, MT7981, MT7986 CVSS 3.1CRITICAL 9.8
TI-2025-14725 Integer overflow in MediaTek MT6781, MT6789, MT6835, MT6855, MT6878, MT6879, MT6886… CVSS 3.1MEDIUM 6.5
TI-2024-13114 Memory corruption in MediaTek MT2735, MT2737, MT6833, MT6835, MT6835T, MT6853, MT6855… CVSS 3.1CRITICAL 9.8
TI-2022-14283 Command injection in MediaTek EN7528, EN7580 CVSS 3.1CRITICAL 9.8
TI-2021-11684 Command injection in MediaTek EN7528, EN7580 CVSS 3.1CRITICAL 9.8

See all 1133 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences