# Remediation Handoff: CVE-2026-100504

## Summary

NVD: Ghidra versions through 12.1.4 contain a stack-based out-of-bounds write vulnerability in the decompiler's leftshift128 function when processing negative shift amounts from p-code. NVD: Attackers can craft malicious binaries with specific instruction sequences that trigger the overflow when decompiled, corrupting memory and potentially achieving code execution. OSV: Ghidra through 12.1.4 Stack-based Buffer Overflow via leftshift128

## Why it matters

CVSS severity is HIGH with score 7.3. EPSS percentile is 0.0205. KEV status is not listed in KEV. Use this as a defensive priority handoff, not as an execution instruction.

## Affected context

* Vendor: unknown
* Product: unknown
* Component: unknown
* Version / CPE / PURL: unknown

## Remediation context

* Recommended route: vendor_patch_or_mitigation
* Vendor/advisory reference: official_reference_present
* Patch status: requires_confirmation
* Fixed version: unknown
* References: https://github.com/NationalSecurityAgency/ghidra, https://github.com/NationalSecurityAgency/ghidra/blob/8b6bbb857accdfa20dc5b2f5dea471178c2e9fbc/Ghidra/Features/Decompiler/src/decompile/cpp/multiprecision.cc#L29-L61, https://github.com/NationalSecurityAgency/ghidra/blob/8b6bbb857accdfa20dc5b2f5dea471178c2e9fbc/Ghidra/Features/Decompiler/src/decompile/cpp/ruleaction.cc#L7848-L7878, https://github.com/NationalSecurityAgency/ghidra/commit/6babe3c1cec7f5ec920dd16cdc86a02893e5b33c

## Human checklist

* Confirm whether the listed product or package is present.
* Confirm affected version.
* Review vendor advisory or official source.
* Confirm patch, fixed version, mitigation, workaround, or monitor-only decision.
* Confirm exposure.
* Document remediation status.

## Safe AI / Codex handoff

* Goal: Prepare a defensive remediation plan for CVE-2026-100504 using only provided public-safe source context and any separate repo context supplied by the user.
* Allowed actions: summarize vendor guidance, prepare a defensive remediation plan, identify affected dependencies only when repo context is separately provided by the user, suggest tests and validation steps, document human verification questions
* Disallowed actions: generate offensive code, provide payloads, scan external targets, change production systems, merge or deploy changes, create GitHub issues or pull requests without explicit separate approval
* Acceptance criteria: Affected product or dependency presence is confirmed by a human., Affected version is confirmed or marked not applicable., Official advisory or source reference is reviewed., Patch, fixed version, mitigation, workaround, or monitor-only decision is documented., Validation steps are proposed without external scanning or production mutation.
* Human approval required: true

## Safety note

This handoff is for defensive triage and remediation planning only. It excludes offensive procedure, payload material, external target scan guidance, and auto-remediation.