Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2021-39793 is a high-severity Out-of-bounds Write (CWE-787) vulnerability in Google Android. Its CVSS base score is 7.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Security Account Manager (T1003.002); ranked in the top 48% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
The vulnerability is an out-of-bounds write in the function kbase_jd_user_buf_pin_pages within mali_kbase_mem.c, caused by a logic error in the code. It affects the Android kernel and is tracked under Android ID A-210470189, with a CVSS 3.1 base score of 7.8 reflecting local attack vector, low complexity, and high impact on confidentiality, integrity, and availability. The underlying weakness is categorized as CWE-787.
A local attacker with no additional execution privileges and without requiring user interaction can exploit the flaw to achieve privilege escalation on the affected system. The issue resides in the Mali kernel driver code path handling user buffer pinning, enabling memory corruption that can be leveraged for elevated access.
The March 2022 Pixel security bulletin addresses the issue through kernel updates for supported Android devices, while CISA lists the CVE in its known exploited vulnerabilities catalog, indicating confirmed real-world exploitation.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2021-26150
Vulnerability Data
In kbase_jd_user_buf_pin_pages of mali_kbase_mem.c, there is a possible out of bounds write due to a logic error in the code. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for…
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exploitation.Product: AndroidVersions: Android kernelAndroid ID: A-210470189References: N/A
- CWE(s)
- KEV Date Added
- 11 April 2022
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Out-of-bounds writes that corrupt control flow or inject shellcode are rendered non-executable by the same memory protections.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Vulnerability scanning and recording can discover out-of-bounds write flaws so they can be remediated.
Patching or replacing vulnerable software directly eliminates known instances of this coding weakness.
Secure-development practices (static analysis, bounds checking, code review) are the primary means of preventing out-of-bounds writes.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.