CVE-2016-2427

Publication date 18 April 2016

Last updated 4 August 2025

Ubuntu priority

Cvss 3 Severity Score

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.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
android	17.10 artful	Not in release
	17.04 zesty	Not affected
	16.10 yakkety	Ignored end of life
	16.04 LTS xenial	Not affected
	15.10 wily	Ignored end of life
	14.04 LTS trusty	Not in release
	12.04 LTS precise	Not in release
bouncycastle	17.10 artful	Not affected
	17.04 zesty	Not affected
	16.10 yakkety	Ignored end of life
	16.04 LTS xenial	Not affected
	15.10 wily	Not affected
	14.04 LTS trusty	Not in release
	12.04 LTS precise	Not affected

Notes

mdeslaur

no reverse depends in main as of 2015-05-05, no equivalent fix in bouncycastle git repo, this is an android issue, and is disputed

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
android	Upstream: https://android.googlesource.com/platform/libcore/+/efd369d996fd38c50a50ea0de8f20507253cb6de Upstream: https://android.googlesource.com/platform/external/bouncycastle/+/b3bddea0f33c0459293c6419569ad151b4a7b44b

Severity score breakdown

Parameter	Value
Base score	5.5 · Medium
Attack vector	Local
Attack complexity	Low
Privileges required	None
User interaction	Required
Scope	Unchanged
Confidentiality	High
Integrity impact	None
Availability impact	None
Vector	CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N