{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","favicon":"https://feed.craftedsignal.io/favicon-32x32.png","feed_url":"https://feed.craftedsignal.io/products/zebra--4.4.0/feed.json","home_page_url":"https://feed.craftedsignal.io/","icon":"https://feed.craftedsignal.io/apple-touch-icon.png","items":[{"_cs_actors":[],"_cs_cpes":["cpe:2.3:a:zebra:zebra:*:*:*:*:*:*:*:*"],"_cs_cves":[{"cvss":7.5,"id":"CVE-2026-104431"}],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":["Zebra (\u003c 6.0.0)","Zebra (\u003c 4.4.0)"],"_cs_severities":["medium"],"_cs_tags":["denial-of-service","vulnerability","blockchain"],"_cs_type":"advisory","_cs_vendors":["Zebra"],"content_html":"\u003cp\u003eZebra versions prior to 6.0.0 contain a denial-of-service (DoS) vulnerability that allows unauthenticated network peers to compromise node stability. The vulnerability stems from the way the node handles mempool transactions; specifically, it allows the submission of non-standard transactions with high signature operation (sigop) counts. These transactions reach the CachedFfiTransaction::is_valid() verification function before standard validation checks are performed. By flooding the node with these computationally expensive transactions, an attacker can saturate the verifier buffer and stall the underlying Tokio workers. This resource exhaustion forces the node to become unresponsive, impacting the availability of the Zebra service. This vulnerability highlights the risk of processing complex transaction data before validating it against standard consensus rules.\u003c/p\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation results in a complete denial of service for the targeted Zebra node. By stalling the Tokio worker threads, the attacker renders the node unable to process legitimate blockchain data, participate in peer-to-peer communication, or perform synchronization tasks, effectively taking the node offline.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cp\u003ePrioritized actions for administrators:\u003c/p\u003e\n\u003cul\u003e\n\u003cli\u003ePatch the affected Zebra software by upgrading to version 6.0.0 or later immediately to address CVE-2026-104431.\u003c/li\u003e\n\u003cli\u003eMonitor network traffic and node logs for an unusual influx of high-sigop transactions or sudden spikes in resource utilization (CPU/Memory) corresponding to transaction validation.\u003c/li\u003e\n\u003cli\u003eIn resource-constrained or critical production environments, implement strict peer admission control or rate limiting for unauthenticated incoming connections to mitigate the impact of malicious transaction bursts until an upgrade is feasible.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-10-02T14:24:57Z","date_published":"2026-10-02T14:24:50Z","id":"https://feed.craftedsignal.io/briefs/2026-10-zebra-dos/","summary":"Zebra versions prior to 6.0.0 are vulnerable to an unauthenticated denial-of-service attack via the submission of non-standard high-sigop P2SH transactions that exhaust system resources.","title":"Denial of Service Vulnerability in Zebra","url":"https://feed.craftedsignal.io/briefs/2026-10-zebra-dos/"}],"language":"en","title":"CraftedSignal Threat Feed - Zebra (\u003c 4.4.0)","version":"https://jsonfeed.org/version/1.1"}