CVE-2020-12856

OpenTrace, as used in COVIDSafe through v1.0.17, TraceTogether, ABTraceTogether, and other applications on iOS and Android, allows remote attackers to conduct long-term re-identification attacks and possibly have unspecified other impact, because of how Bluetooth is used.

Published: 2020-05-18 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2020-12856 is rated High Risk (66.8/100): CVSS Critical severity, with high exploitation likelihood (EPSS 10.76%, 93th percentile). Core evidence: EPSS ranks this CVE among the most likely to be exploited in the near term. Mandatory action: High exploitation likelihood—assess exposure and prioritize remediation.

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-2020-12856

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 2025-11-21 17.76% 10.76% -7.01%
2 2025-11-18 10.76% 17.76% +7.01%
3 2025-07-15 10.76%

Full EPSS history (17 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-12856

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
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.
3.9 5.9 [email protected]
7.5 2.0 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
10.0 6.4 [email protected]

Weakness enumeration for CVE-2020-12856

Affected software / configurations for CVE-2020-12856

Vendor Product Version Raw CPE
alberta abtracetogether cpe:2.3:a:alberta:abtracetogether:-:*:*:*:*:android:*:*
alberta abtracetogether cpe:2.3:a:alberta:abtracetogether:-:*:*:*:*:iphone_os:*:*
health covidsafe <= 1.0.17 cpe:2.3:a:health:covidsafe:*:*:*:*:*:android:*:*
health covidsafe cpe:2.3:a:health:covidsafe:-:*:*:*:*:iphone_os:*:*
tracetogether tracetogether cpe:2.3:a:tracetogether:tracetogether:-:*:*:*:*:android:*:*
tracetogether tracetogether cpe:2.3:a:tracetogether:tracetogether:-:*:*:*:*:iphone_os:*:*

References for CVE-2020-12856

cvelogic Threat Intelligence