MediaTek MT8893 Modem memory corruption

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
9.5$0-$5k3.48

Summaryinfo

A vulnerability marked as very critical has been reported in MediaTek MT2716, MT2735, MT2737, MT6813, MT6833, MT6835, MT6853, MT6855, MT6858, MT6873, MT6875, MT6877, MT6878, MT6879, MT6880, MT6881, MT6883, MT6885, MT6886, MT6889, MT6890, MT6891, MT6893, MT6895, MT6896, MT6897, MT6899, MT6980, MT6982VB, MT6983, MT6985, MT6986, MT6988, MT6989, MT6990, MT6991, MT6993, MT8668, MT8673, MT8675, MT8676, MT8678, MT8755, MT8771, MT8775, MT8791, MT8791T, MT8792, MT8793, MT8795T, MT8796, MT8797, MT8798, MT8863, MT8873, MT8883 and MT8893. Affected by this vulnerability is an unknown functionality of the component Modem. This manipulation causes memory corruption. This vulnerability is tracked as CVE-2026-20503. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability has been found in MediaTek MT2716, MT2735, MT2737, MT6813, MT6833, MT6835, MT6853, MT6855, MT6858, MT6873, MT6875, MT6877, MT6878, MT6879, MT6880, MT6881, MT6883, MT6885, MT6886, MT6889, MT6890, MT6891, MT6893, MT6895, MT6896, MT6897, MT6899, MT6980, MT6982VB, MT6983, MT6985, MT6986, MT6988, MT6989, MT6990, MT6991, MT6993, MT8668, MT8673, MT8675, MT8676, MT8678, MT8755, MT8771, MT8775, MT8791, MT8791T, MT8792, MT8793, MT8795T, MT8796, MT8797, MT8798, MT8863, MT8873, MT8883 and MT8893 and classified as very critical. Affected by this vulnerability is an unknown code of the component Modem. The manipulation with an unknown input leads to a memory corruption vulnerability. The CWE definition for the vulnerability is CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at mediatek.com. This vulnerability is known as CVE-2026-20503 since 11/03/2025. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 09/07/2026).

Applying the patch MOLY01371002 is able to eliminate this problem.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-72196). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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Vendor

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License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 10.0
VulDB Meta Temp Score: 9.5

VulDB Base Score: 10.0
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: MOLY01371002

Timelineinfo

11/03/2025 CVE reserved
09/07/2026 +307 days Advisory disclosed
09/07/2026 +0 days VulDB entry created
09/07/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: mediatek.com
Status: Confirmed

CVE: CVE-2026-20503 (🔒)
GCVE (CVE): GCVE-0-2026-20503
GCVE (VulDB): GCVE-100-399487
EUVD: 🔒

Entryinfo

Created: 09/07/2026 04:10
Updated: 09/07/2026 13:32
Changes: 09/07/2026 04:10 (54), 09/07/2026 13:32 (1)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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