CVE-2020-27485

CVE-2020-27485 is a critical-severity vulnerability in Garmin Forerunner 235 Firmware with a CVSS 3.x base score of 9.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-129.

Key facts

Description

Garmin Forerunner 235 before 8.20 is affected by: Array index error. The component is: ConnectIQ TVM. The attack vector is: To exploit the vulnerability, the attacker must upload a malicious ConnectIQ application to the ConnectIQ store. The ConnectIQ program interpreter fails to check the index provided when accessing the local variable in the LGETV and LPUTV instructions. This provides the ability to both read and write memory outside the bounds of the TVM context allocation. It can be leveraged to construct a use-after-free scenario, leading to a constrained read/write primitive across the entire MAX32630 address space. A successful exploit would allow a ConnectIQ app store application to escape and perform activities outside the restricted application execution environment.

Frequently asked questions

What is CVE-2020-27485?
Garmin Forerunner 235 before 8.20 is affected by: Array index error. The component is: ConnectIQ TVM. The attack vector is: To exploit the vulnerability, the attacker must upload a malicious ConnectIQ application to the ConnectIQ store. The ConnectIQ program interpreter fails to check the index provided when accessing the local variable in the LGETV and LPUTV instructions. This provides the ability to both read and write memory outside the bounds of the TVM context allocation. It can be leveraged to construct a use-after-free scenario, leading to a constrained read/write primitive across the entire MAX32630 address space. A successful exploit would allow a ConnectIQ app store application to escape and perform activities outside the restricted application execution environment.
How severe is CVE-2020-27485?
CVE-2020-27485 has a CVSS 3.x base score of 9.9, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-27485 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-27485?
CVE-2020-27485 affects Garmin Forerunner 235 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-27485?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2020-27485 published?
CVE-2020-27485 was published on 2020-11-16 and last updated on 2026-06-17.

References

Affected products (1)

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