CVE-2021-0325Network attack vector

Remote code execution via unchecked slice index

Published Feb 10, 2021 · Updated Aug 3, 2024

Heap buffer overflow in Android 8.1 through 11 Media Framework allows remote attackers to execute code via a crafted H.264 file. ih264d_parse_slice.c accepts a first_mb_in_slice value equal to the picture's macroblock count, permitting an out-of-range write during slice decoding. Exploitation requires a user to process the file, after which code runs in the context of the privileged media process.

CVSS severity8.8
High
EPSS probability2.20%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Heap buffer overflow in Android 8.1 through 11 Media Framework allows remote attackers to execute code via a crafted H.264 file. ih264d_parse_slice.c accepts a first_mb_in_slice value equal to the picture's macroblock count, permitting an out-of-range write during slice decoding. Exploitation requires a user to process the file, after which code runs in the context of the privileged media process.

The record

CVE
CVE-2021-0325
Published
Feb 10, 2021
Updated
Aug 3, 2024
Vendor
Google Cloud
Product
Android
Classifications
CWE-787, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 10, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=Android-8.1 Android-9 Android-10 Android-11

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Google Cloud · Androidversion=Android-8.1 Android-9 Android-10 Android-11

Published CVSS scores

8.8NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
9.3NVDAV:N/AC:M/Au:N/C:C/I:C/A:C

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write
T1203Exploitation for Client Execution

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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