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Medium ALSA-2021:4586 1 CVE

Moderate: gcc-toolset-11-gcc security update

Published Nov 10, 2021 · Updated Oct 29, 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 18

ReleasePackageFixed in
AlmaLinux · 8 gcc-toolset-11-gcc 11.2.1-1.2.el8_5
AlmaLinux · 8 gcc-toolset-11-gcc-c++ 11.2.1-1.2.el8_5
AlmaLinux · 8 gcc-toolset-11-gcc-gdb-plugin 11.2.1-1.2.el8_5
AlmaLinux · 8 gcc-toolset-11-gcc-gfortran 11.2.1-1.2.el8_5
AlmaLinux · 8 gcc-toolset-11-gcc-plugin-devel 11.2.1-1.2.el8_5
AlmaLinux · 8 gcc-toolset-11-libasan-devel 11.2.1-1.2.el8_5
AlmaLinux · 8 gcc-toolset-11-libatomic-devel 11.2.1-1.2.el8_5
AlmaLinux · 8 gcc-toolset-11-libgccjit 11.2.1-1.2.el8_5
AlmaLinux · 8 gcc-toolset-11-libgccjit-devel 11.2.1-1.2.el8_5
AlmaLinux · 8 gcc-toolset-11-libgccjit-docs 11.2.1-1.2.el8_5
AlmaLinux · 8 gcc-toolset-11-libitm-devel 11.2.1-1.2.el8_5
AlmaLinux · 8 gcc-toolset-11-liblsan-devel 11.2.1-1.2.el8_5
AlmaLinux · 8 gcc-toolset-11-libquadmath-devel 11.2.1-1.2.el8_5
AlmaLinux · 8 gcc-toolset-11-libstdc++-devel 11.2.1-1.2.el8_5
AlmaLinux · 8 gcc-toolset-11-libstdc++-docs 11.2.1-1.2.el8_5
AlmaLinux · 8 gcc-toolset-11-libtsan-devel 11.2.1-1.2.el8_5
AlmaLinux · 8 gcc-toolset-11-libubsan-devel 11.2.1-1.2.el8_5
AlmaLinux · 8 libasan6 11.2.1-1.2.el8_5

Vulnerabilities 1

References

  • report
    https://vulners.com/cve/CVE-2021-42574