CVE-2018-12271

An issue was discovered in the com.getdropbox.Dropbox app 100.2 for iOS. The LAContext class for Biometric (TouchID) validation allows authentication bypass by overriding the LAContext return Boolean value to be "true" because the kSecAccessControlUserPresence protection mechanism is not used. In other words, an attacker could authenticate with an arbitrary fingerprint. NOTE: the vendor indicates that this is not an attack of interest within the context of their threat model, which excludes iOS devices on which a jailbreak has occurred

Published: 2018-06-13 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2018-12271 is rated Low Risk (38/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.43%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2018-12271

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.04% 0.43% +0.39%
2 2025-03-30 0.07% 0.04% -0.04%
3 2025-03-29 — 0.07% —

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2018-12271

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.4 3.0 MEDIUM
CVSS:3.0/AV:P/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:P)
Hands-on access—USB, keyboard, opening the case—not something you do purely over the wire.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 0.5 5.9 [email protected]
6.9 2.0 MEDIUM
AV:L/AC:M/Au:N/C:C/I:C/A:C Click to expand
Access vector (AV:L)
Requires local access to the target system.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:C)
Complete confidentiality impact.
Integrity impact (I:C)
Complete integrity impact.
Availability impact (A:C)
Complete availability impact.
 3.4 10.0 [email protected]

Weakness enumeration for CVE-2018-12271

Affected software / configurations for CVE-2018-12271

Vendor Product Version Raw CPE
dropbox dropbox 100.2 cpe:2.3:a:dropbox:dropbox:100.2:*:*:*:*:iphone_os:*:*

References for CVE-2018-12271

URL Tags
https://gist.github.com/tanprathan/6e8ed195a2e05b7f9d9a342dbdacb349 Issue Tracking Third Party Advisory Tool Signature
https://hackerone.com/reports/363544 Issue Tracking Third Party Advisory
https://www.dropbox.com/s/n880ob3gtvfwryu/20180609_013320.mp4?dl=0 Broken Link Permissions Required
cvelogic Threat Intelligence