Side-channel attack in libgcrypt (Alpine package)

1) Side-channel attack

EUVDB-ID: #VU7299

Risk: Low

CVSSv4.0: 1.7 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2017-9526

CWE-ID: CWE-310 - Cryptographic Issues

Exploit availability: No

Description

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists in libgcrypt's EdDSA implementation. An attacker who learns the EdDSA session key (from side-channel observation during the signing process) can easily recover the long-term secret key.

Mitigation

Install update from vendor's website.

Vulnerable software versions

libgcrypt (Alpine package): 1.6.6-r0 - 1.7.6-r0

CPE2.3

• cpe:2.3:o:alpine:libgcrypt_alpine_package:1.6.6-r0:*:*:*:*:alpine_linux:*:3.2
• cpe:2.3:o:alpine:libgcrypt_alpine_package:1.7.0-r0:*:*:*:*:alpine_linux:*:3.3
• cpe:2.3:o:alpine:libgcrypt_alpine_package:1.7.0-r1:*:*:*:*:alpine_linux:*:3.3

External links

https://git.alpinelinux.org/aports/commit/?id=f11d5afa3b8a26a5fef94feaf00c7a413ef0b62e
https://git.alpinelinux.org/aports/commit/?id=03d53aaa064c5812651cd6cdad8018514d23fa04
https://git.alpinelinux.org/aports/commit/?id=95b3d924de75435596c3a72e003dcdb160de6494
https://git.alpinelinux.org/aports/commit/?id=b95bfcc998819366a8cadce0f079feda32c8c2ab

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.