{"id":56551,"date":"2026-05-24T00:23:56","date_gmt":"2026-05-24T00:23:56","guid":{"rendered":"https:\/\/zero.redgem.net\/?p=56551"},"modified":"2026-05-24T00:23:56","modified_gmt":"2026-05-24T00:23:56","slug":"nousresearch-hermes-agent-slack-agentmattermost-agent-escape-output","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=56551","title":{"rendered":"NousResearch hermes-agent Slack Agent\/Mattermost Agent escape output_CVE-2026-9354"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;A vulnerability was detected in NousResearch hermes-agent up to 2026.4.16. The affected element is an unknown function of the component Slack Agent\/Mattermost Agent. The manipulation of the argument format_message results in escaping of output. The attack can be executed remotely. The exploit is now public and may be used. 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The affected element is an unknown function of the component Slack Agent\/Mattermost Agent. The manipulation&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[6,8,48,12,21,13,7,11,5],"class_list":["post-56551","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-cve","tag-cvss","tag-cvss-69","tag-exploit","tag-medium","tag-news","tag-security","tag-tapic","tag-vulnerability"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.5 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>NousResearch hermes-agent Slack Agent\/Mattermost Agent escape output_CVE-2026-9354 - zero redgem<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/zero.redgem.net\/?p=56551\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"NousResearch hermes-agent Slack Agent\/Mattermost Agent escape output_CVE-2026-9354 - zero redgem\" \/>\n<meta property=\"og:description\" content=\"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;A vulnerability was detected in NousResearch hermes-agent up to 2026.4.16. 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