CVE-2026-20503

MEDIUM
5.3
CVSS Score
Published: September 7, 2026 at 01:57 AM UTC
Updated: September 9, 2026 at 03:15 AM UTC
114 products affected across 1 vendorMT6991 FirmwareMT8668 FirmwareMT6993 Firmware

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Severity
MEDIUM5.3
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

Description

In Modem, there is a possible system crash due to a missing bounds check. This could lead to remote denial of service, 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: MOLY01371002; Issue ID: MSV-9020.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

All versions
mediatek-mt2716 (same device)
All versions
mediatek-mt2735 (same device)
All versions
mediatek-mt2737 (same device)
All versions
mediatek-mt6813 (same device)
All versions
mediatek-mt6833 (same device)
All versions
mediatek-mt6835 (same device)
All versions
mediatek-mt6853 (same device)
All versions
mediatek-mt6855 (same device)
All versions
mediatek-mt6858 (same device)
All versions
mediatek-mt6873 (same device)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (1)

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.3MEDIUMCISA-ADP
Attack Vector
ADJACENT_NETWORK
Complexity
HIGH
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-617

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