UBUNTU-CVE-2026-125709: Buffer Overflow
Published Nov 12, 2026
·Updated
A flaw was found in libstdc++. When a byte-by-byte write operation fails during file stream processing, the library may still append data into the internal memory buffer. An attacker capable of inducing repeated write failures in an affected service can trigger a buffer overflow, potentially resulting in a Denial of Service (DoS) or memory corruption.
Affected Software
157 affected components
ubuntu/gcc-3.3*
ubuntu/gcc-4.7*
ubuntu/gcc-4.8*
ubuntu/gcc-defaults*
ubuntu/gcc-mingw-w64*
ubuntu/gccgo-4.9*
ubuntu/gcc-5*
ubuntu/gcc-5-cross*
ubuntu/gcc-defaults*
ubuntu/gccgo-6*
ubuntu/gcc-3.3*
ubuntu/gcc-4.7*
ubuntu/gcc-4.7-armel-cross*
ubuntu/gcc-4.7-armhf-cross*
ubuntu/gcc-4.8*
ubuntu/gcc-4.8-arm64-cross*
ubuntu/gcc-4.8-armhf-cross*
ubuntu/gcc-4.8-powerpc-cross*
ubuntu/gcc-4.8-ppc64el-cross*
ubuntu/gcc-4.9-cross*
ubuntu/gcc-5-cross-ports*
ubuntu/gcc-arm-linux-androideabi*
ubuntu/gcc-arm-none-eabi*
ubuntu/gcc-avr*
ubuntu/gcc-h8300-hms*
ubuntu/gcc-i686-linux-android*
ubuntu/gcc-m68hc1x*
ubuntu/gcc-mingw-w64*
ubuntu/gcc-msp430*
ubuntu/gcc-snapshot*
ubuntu/gcc-7*
ubuntu/gcc-7-cross*
ubuntu/gcc-8*
ubuntu/gcc-8-cross*
ubuntu/gcc-defaults*
ubuntu/gcc-3.3*
ubuntu/gcc-4.8*
ubuntu/gcc-5*
ubuntu/gcc-5-cross*
ubuntu/gcc-5-cross-ports*
ubuntu/gcc-6-cross*
ubuntu/gcc-6-cross-ports*
ubuntu/gcc-7-cross-ports*
ubuntu/gcc-8-cross-ports*
ubuntu/gcc-arm-none-eabi*
ubuntu/gcc-avr*
ubuntu/gcc-h8300-hms*
ubuntu/gcc-m68hc1x*
ubuntu/gcc-mingw-w64*
ubuntu/gcc-msp430*
ubuntu/gcc-snapshot*
ubuntu/gcc-10*
ubuntu/gcc-10-cross*
ubuntu/gcc-9*
ubuntu/gcc-9-cross*
ubuntu/gcc-defaults*
ubuntu/gcc-10-cross-mipsen*
ubuntu/gcc-10-cross-ports*
ubuntu/gcc-3.3*
ubuntu/gcc-7*
ubuntu/gcc-8*
ubuntu/gcc-8-cross*
ubuntu/gcc-8-cross-ports*
ubuntu/gcc-9-cross-mipsen*
ubuntu/gcc-9-cross-ports*
ubuntu/gcc-arm-none-eabi*
ubuntu/gcc-avr*
ubuntu/gcc-h8300-hms*
ubuntu/gcc-m68hc1x*
ubuntu/gcc-mingw-w64*
ubuntu/gcc-msp430*
ubuntu/gcc-riscv64-unknown-elf*
ubuntu/gcc-snapshot*
ubuntu/gcc-xtensa-lx106*
ubuntu/gcc-10*
ubuntu/gcc-10-cross*
ubuntu/gcc-10-cross-mipsen*
ubuntu/gcc-10-cross-ports*
ubuntu/gcc-11*
ubuntu/gcc-11-cross*
ubuntu/gcc-11-cross-ports*
ubuntu/gcc-12-cross*
ubuntu/gcc-12-cross-ports*
ubuntu/gcc-3.3*
ubuntu/gcc-9*
ubuntu/gcc-9-cross*
ubuntu/gcc-9-cross-mipsen*
ubuntu/gcc-9-cross-ports*
ubuntu/gcc-arm-none-eabi*
ubuntu/gcc-avr*
ubuntu/gcc-defaults*
ubuntu/gcc-h8300-hms*
ubuntu/gcc-m68hc1x*
ubuntu/gcc-mingw-w64*
ubuntu/gcc-msp430*
ubuntu/gcc-or1k-elf*
ubuntu/gcc-riscv64-unknown-elf*
ubuntu/gcc-snapshot*
ubuntu/gcc-xtensa-lx106*
ubuntu/gcc-10*
ubuntu/gcc-10-cross*
ubuntu/gcc-10-cross-mipsen*
ubuntu/gcc-10-cross-ports*
ubuntu/gcc-11*
ubuntu/gcc-11-cross*
ubuntu/gcc-11-cross-mipsen*
ubuntu/gcc-11-cross-ports*
ubuntu/gcc-12-cross*
ubuntu/gcc-12-cross-mipsen*
ubuntu/gcc-12-cross-ports*
ubuntu/gcc-13-cross*
ubuntu/gcc-13-cross-ports*
ubuntu/gcc-3.3*
ubuntu/gcc-9*
ubuntu/gcc-9-cross*
ubuntu/gcc-9-cross-mipsen*
ubuntu/gcc-9-cross-ports*
ubuntu/gcc-arm-none-eabi*
ubuntu/gcc-avr*
ubuntu/gcc-defaults*
ubuntu/gcc-h8300-hms*
ubuntu/gcc-mingw-w64*
ubuntu/gcc-or1k-elf*
ubuntu/gcc-riscv64-unknown-elf*
ubuntu/gcc-snapshot*
ubuntu/gcc-11*
ubuntu/gcc-11-cross*
ubuntu/gcc-11-cross-ports*
ubuntu/gcc-12-cross*
ubuntu/gcc-12-cross-ports*
ubuntu/gcc-13*
ubuntu/gcc-13-cross*
ubuntu/gcc-13-cross-ports*
ubuntu/gcc-arm-none-eabi*
ubuntu/gcc-avr*
ubuntu/gcc-defaults*
ubuntu/gcc-h8300-hms*
ubuntu/gcc-mingw-w64*
ubuntu/gcc-or1k-elf*
ubuntu/gcc-riscv64-unknown-elf*
ubuntu/gcc-snapshot*
ubuntu/gcc-11*
ubuntu/gcc-11-cross*
ubuntu/gcc-11-cross-ports*
ubuntu/gcc-12-cross*
ubuntu/gcc-12-cross-ports*
ubuntu/gcc-13*
ubuntu/gcc-13-cross*
ubuntu/gcc-13-cross-ports*
ubuntu/gcc-arm-none-eabi*
ubuntu/gcc-avr*
ubuntu/gcc-defaults*
ubuntu/gcc-h8300-hms*
ubuntu/gcc-mingw-w64*
ubuntu/gcc-or1k-elf*
ubuntu/gcc-riscv64-unknown-elf*
ubuntu/gcc-snapshot*
Event History
Nov 12, 2026
CVE Published
via OSV·12:00 AM
Data Sourced
via OSV·12:00 AM
DescriptionSeverityAffected Software
Frequently Asked Questions
1
What must an attacker be able to do to exploit this issue?
The attacker must be able to induce repeated byte-by-byte write failures in a service that uses the affected libstdc++ file stream processing. Those failures can cause data to continue accumulating in an internal memory buffer.
2
What could happen if the flaw is exploited?
Repeated induced write failures may trigger a buffer overflow. The stated impacts are denial of service or memory corruption.
3
Which Ubuntu software packages are identified as affected?
The listed software includes ubuntu/gcc-defaults, ubuntu/gcc-mingw-w64, ubuntu/gcc-arm-none-eabi, ubuntu/gcc-avr, ubuntu/gcc-h8300-hms, ubuntu/gcc-snapshot, ubuntu/gcc-3.3, and ubuntu/gcc-riscv64-unknown-elf.