#VU28259 Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) in Gnu Compiler Collection - CVE-2019-15847

Vulnerability identifier: #VU28259

Vulnerability risk: Low

CVSSv4.0: 1.1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2019-15847

CWE-ID: CWE-338

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Gnu Compiler Collection
Client/Desktop applications / Software for system administration

Vendor: GNU

Description

The vulnerability allows an attacker to bypass implemented security restrictions.

The vulnerability exists due to the POWER9 backend in GNU Compiler Collection (GCC) can optimize multiple calls of the __builtin_darn intrinsic into a single call, thus reducing the entropy of the random number generator. This vulnerability may weaken security features that rely on random number generator.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Gnu Compiler Collection: 7.1.0 - 9.2.0

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External links
https://lists.opensuse.org/opensuse-security-announce/2019-10/msg00056.html
https://lists.opensuse.org/opensuse-security-announce/2019-10/msg00057.html
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91481
https://gcc.gnu.org/git/?p=gcc.git&a=commit;h=e99bfdd2a8db732ea84cf0a6486707e5e821ad7e

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

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