MediaTek MT8893 Modem 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.
9.5$0-$5k0.65

Summaryinfo

A vulnerability was found in MediaTek MT2716, MT2735, MT2737, MT6813, MT6815, MT6833, MT6835, MT6853, MT6855, MT6858, MT6873, MT6875, MT6877, MT6878, MT6879, MT6880, MT6881, MT6883, MT6885, MT6886, MT6889, MT6890, MT6891, MT6893, MT6895, MT6896, MT6897, MT6899, MT6980, MT6982, MT6983, MT6985, MT6986, MT6988, MT6989, MT6990, MT6991, MT6993, MT8668, MT8676, MT8678, MT8695, MT8696, MT8755, MT8771, MT8775, MT8791, MT8791T, MT8792, MT8793, MT8796, MT8797, MT8798, MT8863, MT8873, MT8883 and MT8893. It has been rated as very critical. This issue affects some unknown processing of the component Modem. The manipulation leads to out-of-bounds write. This vulnerability is listed as CVE-2026-20520. The attack may be initiated remotely. There is no available exploit. To fix this issue, it is recommended to deploy a patch.

Detailsinfo

A vulnerability was found in MediaTek MT2716, MT2735, MT2737, MT6813, MT6815, MT6833, MT6835, MT6853, MT6855, MT6858, MT6873, MT6875, MT6877, MT6878, MT6879, MT6880, MT6881, MT6883, MT6885, MT6886, MT6889, MT6890, MT6891, MT6893, MT6895, MT6896, MT6897, MT6899, MT6980, MT6982, MT6983, MT6985, MT6986, MT6988, MT6989, MT6990, MT6991, MT6993, MT8668, MT8676, MT8678, MT8695, MT8696, MT8755, MT8771, MT8775, MT8791, MT8791T, MT8792, MT8793, MT8796, MT8797, MT8798, MT8863, MT8873, MT8883 and MT8893 and classified as very critical. This issue affects an unknown function of the component Modem. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. Using CWE to declare the problem leads to CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

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 not needed for exploitation. Patch ID: MOLY01778988; Issue ID: MSV-8897.

It is possible to read the advisory at mediatek.com. The identification of this vulnerability is CVE-2026-20520 since 11/03/2025. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. 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 10/05/2026).

Applying the patch MOLY01778988 is able to eliminate this problem.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

Vendor

Name

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: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

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: MOLY01778988

Timelineinfo

11/03/2025 CVE reserved
10/05/2026 +335 days Advisory disclosed
10/05/2026 +0 days VulDB entry created
10/05/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: mediatek.com
Status: Confirmed

CVE: CVE-2026-20520 (🔒)
GCVE (CVE): GCVE-0-2026-20520
GCVE (VulDB): GCVE-100-413483

Entryinfo

Created: 10/05/2026 04:19
Changes: 10/05/2026 04:19 (54)
Complete: 🔍
Cache ID: 216::103

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