CVE-2021-33839
Luca through 1.7.4 on Android allows remote attackers to obtain sensitive information about COVID-19 tracking because the QR code of a Public Location can be intentionally confused with the QR code of a Private Meeting.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (2.77%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Luca through 1.7.4 on Android allows remote attackers to obtain sensitive information about COVID-19 tracking because the QR code of a Public Location can be intentionally confused with the QR code of a Private Meeting.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- EPSS
- 2.77% probability · 86th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-200
- Affected
- luca-app/luca
- Source
- cve@mitre.org
EPSS 2.8% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://github.com/mame82/misc/blob/master/luca_traceIds.mdThird Party Advisory
- https://luca-app.de/securityoverview/properties/objectives.htmlVendor Advisory
- https://twitter.com/patrick_hennig/status/1387738281757061125Third Party Advisory
- https://youtu.be/jWyDfEB0m08Exploit, Third Party Advisory
- https://github.com/mame82/misc/blob/master/luca_traceIds.mdThird Party Advisory
- https://luca-app.de/securityoverview/properties/objectives.htmlVendor Advisory
- https://twitter.com/patrick_hennig/status/1387738281757061125Third Party Advisory
- https://youtu.be/jWyDfEB0m08Exploit, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.