CVE-2019-15847

Name: CVE-2019-15847
Creator: NVD / NIST
Published: 2019-09-02T23:15:10.837+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 3.21%

Last modified Jun 17, 2026

CVE-2019-15847 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. The POWER9 backend in GNU Compiler Collection (GCC) before version 10 could optimize multiple calls of the __builtin_darn intrinsic into a single call, thus reducing the entropy of the random number generator. This occurred because a volatile operation was not specified. EPSS estimates a 3.21% chance of exploitation in the next 30 days.

Description

The POWER9 backend in GNU Compiler Collection (GCC) before version 10 could optimize multiple calls of the __builtin_darn intrinsic into a single call, thus reducing the entropy of the random number generator. This occurred because a volatile operation was not specified. For example, within a single execution of a program, the output of every __builtin_darn() call may be the same.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS Probability

3.21%

86.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-331

Affected Software

Vendor	Product	Versions
Gnu	Gcc	< 7.5.0
Gnu	Gcc	>= 8.0, < 8.4.0
Gnu	Gcc	>= 9.0, < 9.3.0
Gnu	Gcc	>= 10.0, < 10.1.0
Opensuse	Leap	15.0
Opensuse	Leap	15.1

References

http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00056.htmlMailing List, Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00057.htmlMailing List, Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00058.htmlMailing List, Third Party Advisory
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91481Issue Tracking, Vendor Advisory
http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00056.htmlMailing List, Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00057.htmlMailing List, Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00058.htmlMailing List, Third Party Advisory
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91481Issue Tracking, Vendor Advisory

Timeline

Published: Sep 2, 2019
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2019-15847?

How severe is CVE-2019-15847?

CVE-2019-15847 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 3.21% probability of exploitation in the next 30 days.

How do I fix CVE-2019-15847?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2019-15847?

Run a free Strix scan to check your systems for this vulnerability.

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Source: NVD / NIST