---
id: "CVE-2026-123975"
page: "https://infrastack.ai/live/CVE-2026-123975"
kind: "vulnerability"
aliases: ["CVE-2026-123975"]
title: "Grid Community Toolkit: heap out-of-bounds write lets remote clients crash services"
severity: "high"
cvss: 8.7
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["globus", "globus-gatekeeper", "grid-computing", "gsi", "myproxy", "package"]
not_affected_if: ["no-globus-gss-assist"]
published_at: "2026-11-13T15:17:34+00:00"
first_seen_at: "2026-11-13T15:46:16+00:00"
updated_at: "2026-11-13T15:48:15+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-123975", "first_seen_at": "2026-11-13T15:46:16+00:00"}]
exploit_sources: []
---

# Grid Community Toolkit: heap out-of-bounds write lets remote clients crash services

Link for people: https://infrastack.ai/live/CVE-2026-123975 (this .md is for agents)

Grid Community Toolkit's globus-gss-assist library writes outside a heap buffer when an SSLv2 record length below 3 is received. A remote unauthenticated client can send a crafted GSI handshake record to services such as globus-gatekeeper and myproxy to corrupt heap memory and crash the service.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed globus-gss-assist version and compare it with the fixed version in the product ranges

## Fix

- Grid Community Toolkit: move to `6.2.20261111` or later
- globus-gss-assist: move to `12.9` or later

## Timeline

- 2026-11-13T15:46:16+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-123975

## Documents

- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/grid-community-toolkit-globus-gss-assist-before-12.9-pre-authentication-heap-out-of-bounds-write
- [fix] Patch: github.com https://github.com/gridcf/gct/commit/3df2be4834c146bdcec90009a0f2e5771ff63cca
- [fix] Release notes: github.com https://github.com/gridcf/gct/releases/tag/v6.2.20261111

## From the sources

Grid Community Toolkit before 6.2.20261111 (globus-gss-assist before 12.9) contains a heap out-of-bounds write in globus_gss_assist_token_get_fd() triggered by SSLv2 record lengths below 3. Remote unauthenticated clients can send a crafted GSI handshake record to services like globus-gatekeeper and myproxy to corrupt heap memory and crash the service.

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