CVE-2018-18978
Description
An issue was discovered in the Ascensia Contour NEXT ONE application for Android before 2019-01-15. It has a statically coded encryption key. Extraction of the encryption key is necessary for deciphering communications between this application and the backend server. This, in combination with retrieving any user's encrypted data from the Ascensia cloud through another vulnerability, allows an attacker to obtain and modify any patient's medical information.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
The Ascensia Contour NEXT ONE Android app uses a static encryption key, allowing attackers to decrypt communications and, combined with data retrieval, access and modify patient medical data.
Vulnerability
The Ascensia Contour NEXT ONE Android application, prior to the update on 2019-01-15, contains a statically coded encryption key. This key is used for encrypting communications between the app and the backend server. The key is embedded in the application binary and can be extracted by an attacker.[1]
Exploitation
An attacker can extract the static encryption key from the app. Combined with another vulnerability that allows retrieval of any user's encrypted data from the Ascensia cloud, the attacker can decrypt the data. The Depth Security blog describes bypassing certificate pinning and exploiting additional weaknesses to gain access to encrypted patient data from the cloud server. Once decrypted, the attacker can also modify the data by re-encrypting it with the known key and sending it back.[1]
Impact
Successful exploitation allows an attacker to obtain and modify any patient's stored glucometer readings and other medical information. This could lead to incorrect medical diagnosis or treatment decisions if healthcare providers rely on the tampered data. The attacker can affect all users of the Contour NEXT ONE platform.[1]
Mitigation
The vendor released a software update on or before 2019-01-15 that patches the vulnerability. Users should ensure their Ascensia Contour NEXT ONE Android app is updated to the latest version. No other workarounds are available.[1]
AI Insight generated on May 26, 2026. Synthesized from this CVE's description and the cited reference URLs; citations are validated against the source bundle.
Affected products
2- Ascensia/Contour NEXT ONE applicationdescription
- Range: <2019-01-15
Patches
0No patches discovered yet.
Vulnerability mechanics
Root cause
"A statically coded encryption key and initialization vector are embedded in the Android application binary, allowing anyone who reverse-engineers the app to decrypt communications."
Attack vector
An attacker extracts the statically coded AES key and IV from the Android application binary by decompiling the obfuscated Java code [ref_id=1]. With the key material in hand, the attacker can decrypt any encrypted data retrieved from the Ascensia cloud backend (obtained through a separate vulnerability). This enables the attacker to read and modify any patient's medical information [ref_id=1].
Affected code
The Android application binary contains a class with two obfuscated methods ("a" and "b") that implement AES-CBC-PKCS5Padding encryption/decryption. Two hard-coded strings within the binary serve as the static encryption key and initialization vector [ref_id=1].
What the fix does
The advisory does not describe a specific patch. The recommended remediation is to avoid embedding static cryptographic keys in client-side application binaries. Instead, keys should be derived at runtime or stored in a hardware-backed keystore, and the encryption scheme should use per-session or per-user keys so that compromise of one device does not expose all users' data [ref_id=1].
Preconditions
- inputAttacker must have access to the Android application binary (e.g., by extracting the APK from a rooted device or from an app store)
- authAttacker must have a means to retrieve encrypted user data from the Ascensia cloud (a separate vulnerability)
Generated on May 25, 2026. Inputs: CWE entries + fix-commit diffs from this CVE's patches. Citations validated against bundle.
References
1- depthsecurity.com/blog/medical-exploitation-you-are-now-diabeticmitrex_refsource_MISC
News mentions
0No linked articles in our index yet.