SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2016-2427

The AES-GCM specification in RFC 5084, as used in Android 5.x and 6.x, recommends 12 octets for the aes-ICVlen parameter field, which might make it easier for attackers to defeat a cryptographic protection mechanism and discover an authentication key…

MEDIUM 5.5EPSS 0.42%

Does this matter?

Lower severity and a low EPSS score (0.42%). Track it; it rarely justifies an emergency change on its own.

Description

The AES-GCM specification in RFC 5084, as used in Android 5.x and 6.x, recommends 12 octets for the aes-ICVlen parameter field, which might make it easier for attackers to defeat a cryptographic protection mechanism and discover an authentication key via a crafted application, aka internal bug 26234568. NOTE: The vendor disputes the existence of this potential issue in Android, stating "This CVE was raised in error: it referred to the authentication tag size in GCM, whose default according to ASN.1 encoding (12 bytes) can lead to vulnerabilities. After careful consideration, it was decided that the insecure default value of 12 bytes was a default only for the encoding and not default anywhere else in Android, and hence no vulnerability existed.

CVSS 3.0
5.5 MEDIUMCVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
EPSS
0.42% probability · 35th percentile
CISA KEV
Not listed
Weakness
CWE-200
Affected
bouncycastle/bc-java · google/android
Source
security@android.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.