MediaTek MT8891 vdec use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.2$0-$5k0.00

Summaryinfo

A vulnerability has been found in MediaTek MT6789, MT6855, MT6879, MT6895, MT6983, MT8673, MT8781, MT8795T, MT8798 and MT8891 and classified as problematic. Affected is an unknown function of the component vdec. This manipulation causes use after free. This vulnerability is registered as CVE-2023-20685. The attack needs to be launched locally. No exploit is available. To fix this issue, it is recommended to deploy a patch.

Detailsinfo

A vulnerability classified as problematic was found in MediaTek MT6789, MT6855, MT6879, MT6895, MT6983, MT8673, MT8781, MT8795T, MT8798 and MT8891 (Chip Software). Affected by this vulnerability is an unknown part of the component vdec. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

In vdec, there is a possible use after free due to a race condition. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation. Patch ID: ALPS07608575; Issue ID: ALPS07608575.

The weakness was published 04/07/2023 as ALPS07608575. It is possible to read the advisory at corp.mediatek.com. This vulnerability is known as CVE-2023-20685 since 10/28/2022. The technical details are unknown and an exploit is not publicly available.

Applying the patch ALPS07608575 is able to eliminate this problem.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2023-24864). 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: 5.3
VulDB Meta Temp Score: 5.2

VulDB Base Score: 4.2
VulDB Temp Score: 4.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.4
NVD Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

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: ALPS07608575

Timelineinfo

10/28/2022 🔍
04/07/2023 +161 days 🔍
04/07/2023 +0 days 🔍
08/31/2025 +877 days 🔍

Sourcesinfo

Advisory: ALPS07608575
Status: Confirmed

CVE: CVE-2023-20685 (🔍)
GCVE (CVE): GCVE-0-2023-20685
GCVE (VulDB): GCVE-100-225235
EUVD: 🔍

Entryinfo

Created: 04/07/2023 09:01
Updated: 08/31/2025 20:05
Changes: 04/07/2023 09:01 (40), 02/12/2025 17:31 (26), 08/31/2025 20:05 (1)
Complete: 🔍
Cache ID: 216::103

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

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