In appendFormatV of String8.cpp, there is a possible out of bounds write due to incorrect error handling.

published 2020-10-14 6 y ago modified 2026-06-17 4 mo ago also EUVD-2020-1923

cvss: 7.8; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 18%
public exploits: 0; none known

In appendFormatV of String8.cpp, there is a possible out of bounds write due to incorrect error handling. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android-8.1 Android-9 Android-10 Android-11 Android-8.0Android ID: A-161894517

Patch / fix

links 1

source.android.com/security/bulletin/2020-10-01 advisory

Exploit prediction

0.27% chance of exploitation in the next 30 days, higher than 18% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
NVD	3.1	7.8	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	7.2	AV:L/AC:L/Au:N/C:C/I:C/A:C

Affected products

n/a Android

Classification

Weakness

CWE-755 Improper Handling of Exceptional Conditions
CWE-787 Out-of-bounds Write

References

source.android.com /security/bulletin/2020-10-01
patch, vendor-advisory

Sources

CVE List CVE-2020-0421
NVD CVE-2020-0421

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary