Name:Cisco Secure Firewall - React Server Components RCE Attempt id:d36459b1-7901-401a-a67e-44426c15b168 version:7 date:None author:Nasreddine Bencherchali, Splunk, Talos NTDR status:production type:TTP Description:This analytic detects exploitation activity of CVE-2025-55182 using Cisco Secure Firewall Intrusion Events.
It leverages Cisco Secure Firewall Threat Defense IntrusionEvent logs to identify cases where Snort signature 65554 (React Server Components remote code execution attempt) is triggered
If confirmed malicious, this behavior could be indicative of a potential exploitation of CVE-2025-55182.
Data_source:
search:`cisco_secure_firewall` EventType=IntrusionEvent signature_id = 65554 | fillnull | stats min(_time) as firstTime max(_time) as lastTime values(signature_id) as signature_id values(signature) as signature values(class_desc) as class_desc values(MitreAttackGroups) as MitreAttackGroups values(InlineResult) as InlineResult values(InlineResultReason) as InlineResultReason values(src) as src values(dest_port) as dest_port values(rule) as rule values(transport) as transport values(app) as app by dest | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `cisco_secure_firewall___react_server_components_rce_attempt_filter`
how_to_implement:This search requires Cisco Secure Firewall Threat Defense Logs, which
includes the FileEvent EventType. This search uses an input macro named `cisco_secure_firewall`.
We strongly recommend that you specify your environment-specific configurations
(index, source, sourcetype, etc.) for Cisco Secure Firewall Threat Defense logs. Replace the macro definition
with configurations for your Splunk environment. The search also uses a post-filter
macro designed to filter out known false positives.
The logs are to be ingested using the Splunk Add-on for Cisco Security Cloud (https://splunkbase.splunk.com/app/7404).
The malware & file access policy must also enable logging.
known_false_positives:Security testing or vulnerability scanners might trigger this. Investigate any potential
matches to determine if they're legitimate.
References: -https://react.dev/blog/2025/12/03/critical-security-vulnerability-in-react-server-components -https://nextjs.org/blog/CVE-2025-66478 -https://nvd.nist.gov/vuln/detail/CVE-2025-55182 -https://gist.github.com/maple3142/48bc9393f45e068cf8c90ab865c0f5f3 -https://www.wiz.io/blog/critical-vulnerability-in-react-cve-2025-55182 drilldown_searches: name:'View the detection results for - "$src$" and "$dest$"' search:'%original_detection_search% | search src="$src$" dest="$dest$"' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' name:'View risk events for the last 7 days for - "$src$" and "$dest$"' search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$src$", "$dest$") | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`' earliest_offset:'7d' latest_offset:'0' analytic_story:['React2Shell']
