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Fencer Intel
medium 4.0

CVE-2017-11671 json

Under certain circumstances, the ix86_expand_builtin function in i386.c in GNU Compiler Collection (GCC) version 4.6, 4.7, 4.8, 4.9, 5 befo…

published 2017-07-26 9 y ago modified 2026-06-17 4 mo ago also EUVD-2017-3283

cvss
4.0
version 3.0, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.5%
EPSS 0.5% chance of exploitation in 30 days, percentile 41%
public exploits
0
none known

Summary

Under certain circumstances, the ix86_expand_builtin function in i386.c in GNU Compiler Collection (GCC) version 4.6, 4.7, 4.8, 4.9, 5 before 5.5, and 6 before 6.4 will generate instruction sequences that clobber the status flag of the RDRAND and RDSEED intrinsics before it can be read, potentially causing failures of these instructions to go unreported. This could potentially lead to less randomness in random number generation.

Patch / fix

  • gcc-5 Ubuntu Pro 16.04 LTS 5.4.0-6ubuntu1~16.04.12+esm2
  • gccgo-6 Ubuntu Pro 16.04 LTS 6.0.1-0ubuntu1+esm1

ubuntu advisories UBUNTU-CVE-2017-11671

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • gcc RHEL 7 4.8.5-28.el7
  • cpp RHEL 7 4.8.5-28.el7
  • libgo RHEL 7 4.8.5-28.el7
  • gcc-go RHEL 7 4.8.5-28.el7
  • libgcc RHEL 7 4.8.5-28.el7
  • libitm RHEL 7 4.8.5-28.el7
  • gcc-c++ RHEL 7 4.8.5-28.el7
  • libasan RHEL 7 4.8.5-28.el7

red hat advisories RHSA-2018:0849

  • gcc48 SLES for SAP 12 SP3, SLES for SAP 12 SP2, SLES for SAP 12 SP1 +10 more 4.8.5-31.3.1
  • libffi48 SLE Software Development Kit 12 SP3, SLE Software Development Kit 12 SP2 4.8.5-31.3.1
  • libgcj48 SLED 12 SP3, SLED 12 SP2, SLE Workstation Extension 12 SP3 +3 more 4.8.5-31.3.1
  • gcc48 SLE Software Development Kit 11 SP4 4.8.5-5.3.1

suse advisories SUSE-SU-2017:2526-1SUSE-SU-2017:2380-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2017-11671 updated cvss 5.6

gcc: GCC generates incorrect code for RDRAND/RDSEED intrinsics

  • Red Hat Enterprise Linux Client (v. 7) cpp 4.8.5-28.el7, gcc 4.8.5-28.el7, libgcc 4.8.5-28.el7, libitm 4.8.5-28.el7, libgomp 4.8.5-28.el7, libatomic 4.8.5-28.el7, +3 more Red Hat Enterprise Linux Client Optional (v. 7) libgo 4.8.5-28.el7, gcc-go 4.8.5-28.el7, gcc-c++ 4.8.5-28.el7, libasan 4.8.5-28.el7, libgnat 4.8.5-28.el7, libobjc 4.8.5-28.el7, +6 more Red Hat Enterprise Linux ComputeNode (v. 7) cpp 4.8.5-28.el7, gcc 4.8.5-28.el7, libgcc 4.8.5-28.el7, libitm 4.8.5-28.el7, libgomp 4.8.5-28.el7, libatomic 4.8.5-28.el7, +4 more Red Hat Enterprise Linux ComputeNode Optional (v. 7) libgo 4.8.5-28.el7, gcc-go 4.8.5-28.el7, gcc-c++ 4.8.5-28.el7, libasan 4.8.5-28.el7, libgnat 4.8.5-28.el7, libobjc 4.8.5-28.el7, +5 more Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server (v. 7) cpp 4.8.5-28.el7, gcc 4.8.5-28.el7, libgcc 4.8.5-28.el7, libitm 4.8.5-28.el7, gcc-c++ 4.8.5-28.el7, libgnat 4.8.5-28.el7, +9 more Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server Optional (v. 7) libgo 4.8.5-28.el7, gcc-go 4.8.5-28.el7, libmudflap 4.8.5-28.el7
    +4 more products
    Red Hat Enterprise Linux Server (v. 7) cpp 4.8.5-28.el7, gcc 4.8.5-28.el7, libgcc 4.8.5-28.el7, libitm 4.8.5-28.el7, gcc-c++ 4.8.5-28.el7, libgnat 4.8.5-28.el7, +10 more Red Hat Enterprise Linux Server Optional (v. 7) libgo 4.8.5-28.el7, gcc-go 4.8.5-28.el7, libasan 4.8.5-28.el7, libtsan 4.8.5-28.el7, libmudflap 4.8.5-28.el7 Red Hat Enterprise Linux Workstation (v. 7) cpp 4.8.5-28.el7, gcc 4.8.5-28.el7, libgcc 4.8.5-28.el7, libitm 4.8.5-28.el7, gcc-c++ 4.8.5-28.el7, libgnat 4.8.5-28.el7, +10 more Red Hat Enterprise Linux Workstation Optional (v. 7) libgo 4.8.5-28.el7, gcc-go 4.8.5-28.el7, libasan 4.8.5-28.el7, libtsan 4.8.5-28.el7, libmudflap 4.8.5-28.el7
    fixed: vendor fix RHSA-2018:0849
  • Red Hat Enterprise Linux 5 gcc, gcc44, compat-gcc-32, compat-gcc-34, compat-gcc-295, compat-gcc-296 Red Hat Enterprise Linux 6 cpp, gcc, libgcc, libgcj, libitm, gcc-c++, +23 more Red Hat Enterprise Linux 7 compat-gcc-44, compat-libf2c-34, compat-gcc-44-c++, compat-gcc-44-gfortran
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

0.47% chance of exploitation in the next 30 days, higher than 41% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
NVD 3.0 4.0 CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
NVD 2.0 2.1 AV:L/AC:L/Au:N/C:P/I:N/A:N

Classification

Weakness
  • CWE-338 Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.