CVE-2026-84887Public exploitNetwork attack vectorHinoki check available

Authenticated workflow hang via unbounded GUI action

Published Sep 2, 2026 · Updated Sep 3, 2026

Denial of service in Simular Agent S 0.3.0 through 0.3.2 allows remote authenticated users to hang an agent run via a crafted GUI action. The grounding.py workflow evaluates model-generated action parameters without a time or resource budget, so a long agent.wait action blocks execution. Access to submit model input is required; the demonstrated result stalls the current workflow rather than reading or altering data.

CVSS severityUnavailable
Unscored
EPSS probability0.33%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Denial of service in Simular Agent S 0.3.0 through 0.3.2 allows remote authenticated users to hang an agent run via a crafted GUI action. The grounding.py workflow evaluates model-generated action parameters without a time or resource budget, so a long agent.wait action blocks execution. Access to submit model input is required; the demonstrated result stalls the current workflow rather than reading or altering data.

The record

CVE
CVE-2026-84887
Published
Sep 2, 2026
Updated
Sep 3, 2026
Vendor
Simular
Product
Agent S
Classifications
CWE-404, T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 2, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 3, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0.3.0
  2. Affected versionversion=0.3.1
  3. Affected versionversion=0.3.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Simular · Agent Sversion=0.3.0; version=0.3.1; version=0.3.2

Published CVSS scores

5.3VulDB CNACVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
4.0VulDB CNAAV:N/AC:L/Au:S/C:N/I:N/A:P/E:POC/RL:ND/RC:UR
4.3VulDB CNACVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:X/RC:R
4.3VulDB CNACVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:X/RC:R

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-404Improper Resource Shutdown or Release
T1499.004Application or System Exploitation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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