VDB-223876 · CVE-2023-21076 · A-261857623

Google Android nan.cpp createTransmitFollowupRequest out-of-bounds write

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	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.
5.3	$0-$5k	0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in Google Android. This issue affects the function createTransmitFollowupRequest of the file nan.cpp. Executing a manipulation can lead to out-of-bounds write. This vulnerability is handled as CVE-2023-21076. It is possible to launch the attack on the local host. There is not any exploit available. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability classified as critical was found in Google Android (Smartphone Operating System) (affected version not known). This vulnerability affects the function createTransmitFollowupRequest of the file nan.cpp. 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 createTransmitFollowupRequest of nan.cpp, there is a possible out of bounds write due to a heap buffer overflow. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android kernelAndroid ID: A-261857623References: N/A

The weakness was released 03/25/2023 as A-261857623. The advisory is shared for download at source.android.com. This vulnerability was named CVE-2023-21076 since 11/03/2022. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 09/10/2025). It is expected to see the exploit prices for this product increasing in the near future.

Applying a patch is able to eliminate this problem.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2023-25244). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Smartphone Operating System

Vendor

Google

Name

Android

License

free

Website

Vendor: https://www.google.com/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

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

NVD Base Score: 6.7
NVD Vector: 🔍

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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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: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Timelineinfo

11/03/2022 🔍
03/25/2023 +142 days 🔍
03/25/2023 +0 days 🔍
09/10/2025 +900 days 🔍

Sourcesinfo

Vendor: google.com

Advisory: A-261857623
Status: Confirmed

CVE: CVE-2023-21076 (🔍)
GCVE (CVE): GCVE-0-2023-21076
GCVE (VulDB): GCVE-100-223876
EUVD: 🔍
scip Labs: https://www.scip.ch/en/?labs.20150917

Entryinfo

Created: 03/25/2023 08:05
Updated: 09/10/2025 09:15
Changes: 03/25/2023 08:05 (42), 04/14/2023 13:34 (11), 09/10/2025 09:15 (16)
Complete: 🔍
Cache ID: 216::103