Cyber Resilience

CVE-2021-33838

HighPublic PoC

Published: 04 June 2021

Published
04 June 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.0117 79.1th percentile
Risk Priority 16 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-33838 is a high-severity Observable Discrepancy (CWE-203) vulnerability in Luca-App Luca. Its CVSS base score is 7.5 (High).

Operationally, ranked in the top 20.9% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

Luca through 1.7.4 on Android allows remote attackers to obtain sensitive information about COVID-19 tracking because requests related to Check-In State occur shortly after requests for Phone Number Registration.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

luca-app
luca
≤ 1.7.4

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.

addresses: CWE-203

Misdirection can normalize or falsify responses to eliminate observable discrepancies that aid reconnaissance.

addresses: CWE-203

Observable discrepancies in system behavior can be modulated to create covert storage or timing channels; the required analysis detects and constrains such avenues.

addresses: CWE-203

Prevents attackers from using observable differences in error responses to infer internal system details or state.

References