MediaTek MT8893 Base Station out-of-bounds write

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.
9.4$0-$5k2.75

Summaryinfo

A vulnerability labeled as critical has been found in MediaTek MT2735, MT2737, MT6813, MT6833, MT6833P, MT6835, MT6835T, MT6853, MT6853T, MT6855, MT6855T, MT6873, MT6875, MT6875T, MT6877, MT6877T, MT6877TT, MT6878, MT6878M, MT6879, MT6880, MT6883, MT6885, MT6886, MT6889, MT6890, MT6891, MT6893, MT6895, MT6895TT, MT6896, MT6897, MT6899, MT6980, MT6980D, MT6983, MT6983T, MT6985, MT6985T, MT6989, MT6989T, MT6990, MT6991, MT8668, MT8673, MT8675, MT8676, MT8678, MT8755, MT8771, MT8775, MT8791, MT8791T, MT8792, MT8793, MT8795T, MT8797, MT8798, MT8863, MT8873, MT8883 and MT8893. Affected by this issue is some unknown functionality of the component Base Station Handler. Executing a manipulation can lead to out-of-bounds write. This vulnerability appears as CVE-2026-20433. The attack may be performed from remote. There is no available exploit. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability classified as very critical was found in MediaTek MT2735, MT2737, MT6813, MT6833, MT6833P, MT6835, MT6835T, MT6853, MT6853T, MT6855, MT6855T, MT6873, MT6875, MT6875T, MT6877, MT6877T, MT6877TT, MT6878, MT6878M, MT6879, MT6880, MT6883, MT6885, MT6886, MT6889, MT6890, MT6891, MT6893, MT6895, MT6895TT, MT6896, MT6897, MT6899, MT6980, MT6980D, MT6983, MT6983T, MT6985, MT6985T, MT6989, MT6989T, MT6990, MT6991, MT8668, MT8673, MT8675, MT8676, MT8678, MT8755, MT8771, MT8775, MT8791, MT8791T, MT8792, MT8793, MT8795T, MT8797, MT8798, MT8863, MT8873, MT8883 and MT8893. This vulnerability affects an unknown part of the component Base Station Handler. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. The CWE definition for the vulnerability is CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

In Modem, there is a possible out of bounds write due to a missing bounds check. This could lead to remote escalation of privilege, if a UE has connected to a rogue base station controlled by the attacker, with no additional execution privileges needed. User interaction is needed for exploitation. Patch ID: MOLY01088681; Issue ID: MSV-4460.

The advisory is shared for download at corp.mediatek.com. This vulnerability was named CVE-2026-20433 since 11/03/2025. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 04/07/2026).

Applying the patch MSV-4460 is able to eliminate this problem.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-19568). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Vendor

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.8
VulDB Meta Temp Score: 9.4

VulDB Base Score: 9.8
VulDB Temp Score: 9.4
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: Out-of-bounds write
CWE: CWE-787 / 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: MSV-4460

Timelineinfo

11/03/2025 CVE reserved
04/07/2026 +154 days Advisory disclosed
04/07/2026 +0 days VulDB entry created
04/07/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: MSV-4460
Status: Confirmed

CVE: CVE-2026-20433 (🔒)
GCVE (CVE): GCVE-0-2026-20433
GCVE (VulDB): GCVE-100-355708
EUVD: 🔒

Entryinfo

Created: 04/07/2026 07:21
Updated: 04/07/2026 08:30
Changes: 04/07/2026 07:21 (56), 04/07/2026 08:30 (1)
Complete: 🔍
Cache ID: 216:EB0:103

Once again VulDB remains the best source for vulnerability data.

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