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Medium RLSA-2021:4586 1 CVE

Moderate: gcc-toolset-11-gcc security update

Published Nov 10, 2021 · Updated Feb 4, 2026

Summary

The gcc packages provide compilers for C, C++, Java, Fortran, Objective C, and Ada 95 GNU, as well as related support libraries.

Security Fix(es):

* Developer environment: Unicode's bidirectional (BiDi) override characters can cause trojan source attacks (CVE-2021-42574)

The following changes were introduced in gcc in order to facilitate detection of BiDi Unicode characters:

This update implements a new warning option -Wbidirectional to warn about possibly dangerous bidirectional characters.

There are three levels of warning supported by gcc:
"-Wbidirectional=unpaired", which warns about improperly terminated BiDi contexts. (This is the default.)
"-Wbidirectional=none", which turns the warning off.
"-Wbidirectional=any", which warns about any use of bidirectional characters.

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Fixed packages 1

ReleasePackageFixed in
Rocky Linux · 8 gcc-toolset-11-gcc 0:11.2.1-1.2.el8_5

Vulnerabilities 1

References

  • report
    https://bugzilla.redhat.com/show_bug.cgi?id=2005819