MediaTek MT8883 Modem out-of-bounds write

CVSS Meta Temp Score
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Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
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-$5k0.81-

Summaryinfo

A vulnerability was found in MediaTek MT2716, MT6813, MT6815, MT6835, MT6858, MT6878, MT6881, MT6897, MT6899, MT6982, MT6986, MT6988, MT6991, MT6993, MT8668, MT8676, MT8678, MT8755, MT8775, MT8792, MT8793, MT8863, MT8873, MT8875 and MT8883. It has been declared as very critical. The impacted element is an unknown function of the component Modem. Such manipulation leads to out-of-bounds write. This vulnerability is uniquely identified as CVE-2026-20557. The attack can be launched remotely. No exploit exists. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability was found in MediaTek MT2716, MT6813, MT6815, MT6835, MT6858, MT6878, MT6881, MT6897, MT6899, MT6982, MT6986, MT6988, MT6991, MT6993, MT8668, MT8676, MT8678, MT8755, MT8775, MT8792, MT8793, MT8863, MT8873, MT8875 and MT8883. It has been rated as very critical. Affected by this issue is some unknown processing 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. 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 not needed for exploitation. Patch ID: MOLY01877236; Issue ID: MSV-9804.

The advisory is available at mediatek.com. This vulnerability is handled as CVE-2026-20557 since 11/03/2025. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 11/02/2026).

Applying the patch MOLY01877236 is able to eliminate this problem.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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
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: MOLY01877236

Timelineinfo

11/03/2025 CVE reserved
11/02/2026 +364 days Advisory disclosed
11/02/2026 +0 days VulDB entry created
11/02/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: mediatek.com
Status: Confirmed

CNA: MediaTek
CVE: CVE-2026-20557 (🔒)

GCVE (CVE): GCVE-0-2026-20557
GCVE (VulDB): GCVE-100-429722

Entryinfo

Created: 11/02/2026 04:01
Changes: 11/02/2026 04:01 (54)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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