Answer in brief
CVE-2026-121997 records a High severity (CVSS 8.1) vulnerability in Gdb: gdbserver: heap buffer overflow in cmd_qtdpsrc via qtdpsrc declared/actual length mismatch. The current sources do not mark it as known exploited. The current feed maps Red Hat/gcc-toolset-14-gdb (generic), Red Hat/gcc-toolset-15-gdb (generic), Red Hat/gdb (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 8.1. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Red Hat/gcc-toolset-14-gdb (generic), Red Hat/gcc-toolset-15-gdb (generic), Red Hat/gdb (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Red Hat/gcc-toolset-14-gdbgeneric | * | Not reported |
| Red Hat/gcc-toolset-15-gdbgeneric | * | Not reported |
| Red Hat/gdbgeneric | * | Not reported |
Published upstream
Nov 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Nov 5, 2026
A heap buffer overflow in gdbserver's QTDPsrc packet handler allows an unauthenticated remote attacker to achieve native code execution in the gdbserver process. The vulnerability results from a mismatch between a packet's declared source length and the actual data length, causing hex2bin to write beyond the allocated heap buffer.
Quoted source text, attributed separately from HOL analysis.