CVE-2026-53851
OpenClaw < 2026.5.12 - Slack Reaction Event Notification Bypass
OpenClaw before 2026.5.12 contains a notification bypass vulnerability allowing Slack reaction events to enter the agent pipeline despite disabled reaction notifications. Attackers can trigger unintended agent processing by sending reaction events when the feature is enabled, potentially leading to unauthorized processing of lower-trust input.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
6.3
OpenClaw < 2026.5.12 - Slack Reaction Event Notification Bypass
OpenClaw before 2026.5.12 contains a notification bypass vulnerability allowing Slack reaction events to enter the agent pipeline despite disabled reaction notifications. Attackers can trigger unintended agent processing by sending reaction events when the feature is enabled, potentially leading to unauthorized processing of lower-trust input.
- Record
CVE-2026-53851- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-862
- Updated
- 2026-11-02
EUVDEUVD-2026-37153
6.3
OpenClaw before 2026.5.12 contains a notification bypass vulnerability allowing Slack reaction events to enter the agent pipeline despite disabled reaction notifications. Attackers can trigger unintended agent processing by sending reaction events when the feature is enabled, potentially leading to unauthorized processing of lower-trust input.
- Record
EUVD-2026-37153- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-c8w7-9w9h-x69q
6.3
Duplicate Advisory: Slack reaction events could ignore reaction notification settings
Duplicate Advisory
This advisory has been withdrawn because it is a duplicate of GHSA-fcvx-5cxc-v5p8. This link is maintained to preserve external references.
Original Description
OpenClaw before 2026.5.12 contains a notification bypass vulnerability allowing Slack reaction events to enter the agent pipeline despite disabled reaction notifications. Attackers can trigger unintended agent processing by sending reaction events when the feature is enabled, potentially leading to unauthorized processing of lower-trust input.
- Record
GHSA-c8w7-9w9h-x69q- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-862
- Updated
- 2026-11-02
GitHub AdvisoriesGHSA-fcvx-5cxc-v5p8
6.3
OpenClaw: Slack reaction events could ignore reaction notification settings
Summary
Slack reaction events could ignore reaction notification settings. In affected versions, a Slack reaction event delivered to the configured app could enter the agent pipeline even when reaction notifications were disabled.
This advisory is scoped to the named feature and configuration. It does not change OpenClaw's trusted-operator model: authenticated Gateway operators, installed plugins, and intentional local execution surfaces remain trusted unless a separate policy, approval, allowlist, sandbox, or auth boundary is crossed.
Impact
When the affected feature is enabled and reachable, this could trigger unintended agent processing for reaction events. Practical impact depends on the operator's configuration and whether lower-trust input can reach that path.
Patched Versions
The first stable patched version is 2026.5.12.
Mitigations
disable or restrict Slack reaction event subscriptions until patched if this path is not needed. As general hardening, keep channel and tool allowlists narrow, avoid sharing one Gateway between mutually untrusted users, and disable the affected feature when it is not needed.
- Record
GHSA-fcvx-5cxc-v5p8- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-285
- Updated
- 2026-11-02
NVD
6.3
OpenClaw before 2026.5.12 contains a notification bypass vulnerability allowing Slack reaction events to enter the agent pipeline despite disabled reaction notifications. Attackers can trigger unintended agent processing by sending reaction events when the feature is enabled, potentially leading to unauthorized processing of lower-trust input.
- Record
CVE-2026-53851- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-862
- Updated
- 2026-11-02
OSV
6.3
OpenClaw < 2026.5.12 - Slack Reaction Event Notification Bypass
OpenClaw before 2026.5.12 contains a notification bypass vulnerability allowing Slack reaction events to enter the agent pipeline despite disabled reaction notifications. Attackers can trigger unintended agent processing by sending reaction events when the feature is enabled, potentially leading to unauthorized processing of lower-trust input.
- Record
CVE-2026-53851- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-862
- Updated
- 2026-11-02
OSVGHSA-c8w7-9w9h-x69q
6.3
Duplicate Advisory: Slack reaction events could ignore reaction notification settings
Duplicate Advisory
This advisory has been withdrawn because it is a duplicate of GHSA-fcvx-5cxc-v5p8. This link is maintained to preserve external references.
Original Description
OpenClaw before 2026.5.12 contains a notification bypass vulnerability allowing Slack reaction events to enter the agent pipeline despite disabled reaction notifications. Attackers can trigger unintended agent processing by sending reaction events when the feature is enabled, potentially leading to unauthorized processing of lower-trust input.
- Record
GHSA-c8w7-9w9h-x69q- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-862
- Updated
- 2026-11-02
OSVGHSA-fcvx-5cxc-v5p8
6.3
OpenClaw: Slack reaction events could ignore reaction notification settings
Summary
Slack reaction events could ignore reaction notification settings. In affected versions, a Slack reaction event delivered to the configured app could enter the agent pipeline even when reaction notifications were disabled.
This advisory is scoped to the named feature and configuration. It does not change OpenClaw's trusted-operator model: authenticated Gateway operators, installed plugins, and intentional local execution surfaces remain trusted unless a separate policy, approval, allowlist, sandbox, or auth boundary is crossed.
Impact
When the affected feature is enabled and reachable, this could trigger unintended agent processing for reaction events. Practical impact depends on the operator's configuration and whether lower-trust input can reach that path.
Patched Versions
The first stable patched version is 2026.5.12.
Mitigations
disable or restrict Slack reaction event subscriptions until patched if this path is not needed. As general hardening, keep channel and tool allowlists narrow, avoid sharing one Gateway between mutually untrusted users, and disable the affected feature when it is not needed.
- Record
GHSA-fcvx-5cxc-v5p8- CVSS 4.0
- 6.3 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-285
- Updated
- 2026-11-02
Affected products
Affected packages
History
| Recorded | Changed | Sources |
|---|---|---|
| affected | ||
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-53851 is a medium vulnerability (CVSS 6.3) in Openclaw, published June 16, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.19%, the 8th percentile. Fixed in openclaw 2026.5.12.
References
github.com/openclaw/openclaw/security/advisories/GHSA-fcvx-5cxc-v5p8
vulncheck.com/advisories/openclaw-slack-reaction-event-notification-bypass
nvd.nist.gov/vuln/detail/CVE-2026-53851
github.com/advisories/GHSA-c8w7-9w9h-x69q
github.com/advisories/GHSA-fcvx-5cxc-v5p8
github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53851.json
github.com/openclaw/openclaw