Medium severity · published Sep 7, 2026
CVE-2026-20503
In Modem, there is a possible system crash due to a missing bounds check
5.3
CVSS
0.3%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Adjacent
Complexity
High
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 21% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MC
MediaTek chipset · MediaTek, Inc.
MT2716; MT2735; MT2737; MT6813; MT6833; MT6835; +34 more · source: vendor
MF
Mt2716 Firmware · Mediatek
All versions, or not specified · source: NVD
MF
Mt2735 Firmware · Mediatek
All versions, or not specified · source: NVD
MF
Mt2737 Firmware · Mediatek
All versions, or not specified · source: NVD
MF
Mt6813 Firmware · Mediatek
All versions, or not specified · source: NVD
MF
Mt6833 Firmware · Mediatek
All versions, or not specified · source: NVD
MF
Mt6835 Firmware · Mediatek
All versions, or not specified · source: NVD
MF
Mt6853 Firmware · Mediatek
All versions, or not specified · source: NVD
MF
Mt6855 Firmware · Mediatek
All versions, or not specified · source: NVD
MF
Mt6858 Firmware · Mediatek
All versions, or not specified · source: NVD
MF
Mt6873 Firmware · Mediatek
All versions, or not specified · source: NVD
MF
Mt6875 Firmware · Mediatek
All versions, or not specified · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-20503
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-20503
Vendor Advisory
https://www.mediatek.com/product-security-bulletin/September-2026
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