VulnerabilityPublished 20 Jun 2025

CVE-2025-32878: Improper Certificate Validation

Source CVE Database V5

Not known to be exploited · CVSS 9.8 Critical.

Data as of 26 Oct 2026, 13:47 UTC

CVSS 3.1 base score

9.8Critical

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.4% chance of exploitation in 30 days – higher than 35% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: High
Availability: High

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 20 Jun 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

AI-suggested

To mitigate this vulnerability, organizations and users should: 1) Immediately restrict the use of COROS PACE 3 devices on sensitive or enterprise networks until a firmware update is available. 2) Monitor network traffic for unusual TLS connections or attempts to intercept device communications, employing network intrusion detection systems (NIDS) with TLS anomaly detection capabilities. 3) Employ network segmentation to isolate IoT and wearable devices from critical infrastructure. 4) Encourage COROS to release a firmware update that enforces strict X.509 certificate validation, including certificate chain verification and revocation checks. 5) Use endpoint security solutions that can detect abnormal behavior on devices, such as unexpected API token usage or unauthorized firmware downloads. 6) Educate users about the risks of connecting devices to untrusted or public Wi-Fi networks, which are common vectors for MitM attacks. 7) Where possible, implement multi-factor authentication and token expiration policies on backend APIs to limit the impact of stolen tokens. 8) Conduct regular security assessments of IoT devices and their communication protocols to identify and remediate similar weaknesses proactively.

Description

An issue was discovered on COROS PACE 3 devices through 3.0808.0. It implements a function to connect the watch to a WLAN. This function is mainly for downloading firmware files. Before downloading firmware files, the watch requests some information about the firmware via HTTPS from the back-end API. However, the X.509 server certificate within the TLS handshake is not validated by the device. This allows an attacker within an active machine-in-the-middle position, using a TLS proxy and a self-signed certificate, to eavesdrop and manipulate the HTTPS communication. This could be abused, for example, for stealing the API access token of the assigned user account.

Impact

For European organizations, especially those involved in sports, fitness, or health sectors where COROS PACE 3 devices might be used for employee wellness programs or customer engagement, this vulnerability poses a risk to user data confidentiality and system integrity. Attackers exploiting this flaw could intercept sensitive user information or hijack user sessions by stealing API tokens, potentially leading to unauthorized access to personal health data or corporate systems integrated with the device's backend services. This could result in privacy violations, regulatory non-compliance (e.g., GDPR breaches), reputational damage, and financial losses. Additionally, if attackers manipulate firmware downloads, they could deploy malicious firmware updates, compromising device functionality or creating persistent backdoors. The impact extends beyond individual users to organizational security posture, especially if devices are connected to enterprise networks or used in critical operational contexts.

Summary

CVE-2025-32878 is a security vulnerability identified in COROS PACE 3 smartwatches up to firmware version 3.0808.0. The vulnerability arises from improper validation of the X.509 server certificate during the TLS handshake when the device connects to a WLAN to download firmware updates. Specifically, the device does not verify the authenticity of the server certificate, allowing an attacker positioned as a man-in-the-middle (MitM) to intercept and manipulate HTTPS communications by presenting a self-signed or otherwise invalid certificate. This flaw enables the attacker to eavesdrop on sensitive data exchanged between the watch and the backend API, including the potential theft of API access tokens associated with user accounts. These tokens could then be used to impersonate the user or gain unauthorized access to backend services. The vulnerability affects the confidentiality and integrity of the communication channel and could lead to further exploitation if attackers leverage stolen tokens for malicious activities. The lack of certificate validation is a critical cryptographic failure that undermines the security guarantees of TLS, exposing the device and its users to significant risks. No known exploits have been reported in the wild as of the publication date, and no patches or mitigations have been officially released yet.

CWE-295Improper Certificate Validation (opens in a new tab)
Base weaknessOWASP Top 10 A07:2025: Authentication Failures (opens in a new tab)
The product does not validate, or incorrectly validates, a certificate.
Architecture and Design · Implementation
Certificates should be carefully managed and checked to assure that data are encrypted with the intended owner's public key.
Implementation
If certificate pinning is being used, ensure that all relevant properties of the certificate are fully validated before the certificate is pinned, including the hostname.
OWASP Cheat Sheets
Transport Layer Protection (opens in a new tab)
TLS Cipher String (opens in a new tab)
OWASP Authentication (opens in a new tab)
OWASP ASVS 4.0.3
V9.2.1 (opens in a new tab)
V1.9.2 (opens in a new tab)
V2.8.5 (opens in a new tab)
Attack patterns
Creating a Rogue Certification Authority Certificate (opens in a new tab)
Signature Spoofing by Improper Validation (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Description

AI analysisMachine-generated, updated 20 Jun 2025, 14:02 UTC

WeaknessesCWE-295

Technical details

References

Community reviews

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