{"id":44926,"date":"2025-05-27T18:57:15","date_gmt":"2025-05-27T18:57:15","guid":{"rendered":""},"modified":"2025-09-26T20:58:50","modified_gmt":"2025-09-27T02:58:50","slug":"cve-2025-47277-critical-vulnerability-in-vllm-s-pyncclpipe-kv-cache-transfer-integration","status":"publish","type":"post","link":"https:\/\/www.ameeba.com\/blog\/cve-2025-47277-critical-vulnerability-in-vllm-s-pyncclpipe-kv-cache-transfer-integration\/","title":{"rendered":"<strong>CVE-2025-47277: Critical Vulnerability in vLLM\u2019s `PyNcclPipe` KV Cache Transfer Integration<\/strong>"},"content":{"rendered":"<p><strong>Overview<\/strong><\/p>\n<p>The vulnerability CVE-2025-47277 is a highly critical security flaw found in the vLLM, an inference and serving engine for large language models. Specifically, the vulnerability affects the `PyNcclPipe` KV cache transfer integration with the V0 engine in versions 0.6.5 through 0.8.4. The exploitation of this <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-4809-critical-vulnerability-in-tenda-ac7-router-leads-to-system-compromise\/\"  data-wpil-monitor-id=\"50582\">vulnerability could potentially lead to system<\/a> compromise or data leakage, posing significant risks to any environment using the affected configurations. The <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-47577-severe-unrestricted-file-upload-vulnerability-in-ti-woocommerce-wishlist\/\"  data-wpil-monitor-id=\"52099\">severity of this vulnerability<\/a> underscores the importance of immediate action to mitigate the risks.<\/p>\n<p><strong>Vulnerability Summary<\/strong><\/p>\n<p>CVE ID: CVE-2025-47277<br \/>\nSeverity: Critical (CVSS: 9.8)<br \/>\nAttack Vector: Network<br \/>\nPrivileges Required: None<br \/>\nUser Interaction: None<br \/>\nImpact: <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-39401-unrestricted-file-upload-leading-to-potential-system-compromise-in-mojoomla-wpams\/\"  data-wpil-monitor-id=\"52100\">System Compromise<\/a> and Data Leakage<\/p>\n<p><strong>Affected Products<\/strong><\/p><div id=\"ameeb-2522396017\" class=\"ameeb-content-2 ameeb-entity-placement\"><div style=\"border-left: 4px solid #555; padding-left: 20px; margin: 48px 0; font-family: Roboto, sans-serif; color: #ffffff; line-height: 1.6; max-width: 700px;\">\r\n  <h2 style=\"margin-top: 0; font-size: 20px; font-weight: 600; display: flex; align-items: center;\">\r\n    <a href=\"https:\/\/www.ameeba.com\/chat\" style=\"display: inline-flex; align-items: center; margin-right: 8px;\">\r\n      <img decoding=\"async\" src=\"https:\/\/www.ameeba.com\/blog\/wp-content\/uploads\/2025\/10\/Best-App-icon-Ameeba.png\" alt=\"Ameeba Chat Icon\" style=\"width: 40px; height: 40px;\" \/>\r\n    <\/a>\r\n    A new way to communicate\r\n  <\/h2>\r\n\r\n  <p style=\"margin-bottom: 12px;\">\r\n    Ameeba Chat is built on encrypted identity, not personal profiles.\r\n  <\/p>\r\n\r\n  <p style=\"margin-bottom: 16px;\">\r\n    Message, call, share files, and coordinate with identities kept separate.\r\n  <\/p>\r\n\r\n  <ul style=\"list-style: none; padding-left: 0; margin-bottom: 20px;\">\r\n    <li>\u2022 Encrypted identity<\/li>\r\n    <li>\u2022 Ameeba Chat authenticates access<\/li>\r\n    <li>\u2022 Aliases and categories<\/li>\r\n    <li>\u2022 End-to-end encrypted chat, calls, and files<\/li>\r\n    <li>\u2022 Secure notes for sensitive information<\/li>\r\n  <\/ul>\r\n\r\n  <p style=\"font-style: italic; font-weight: 600; margin-bottom: 24px;\">\r\n    Private communication, rethought.\r\n  <\/p>\r\n\r\n  <div style=\"display: flex; flex-wrap: wrap; gap: 12px;\">\r\n    <a href=\"https:\/\/www.ameeba.com\/chat\/download\" style=\"background-color: #ffffff; color: #000000; padding: 10px 20px; text-decoration: none; border-radius: 6px; font-weight: 500;\">Download Ameeba Chat<\/a>\r\n    <a href=\"https:\/\/www.ameeba.com\/chat\" style=\"border: 1px solid #ffffff; color: #ffffff; padding: 10px 20px; text-decoration: none; border-radius: 6px; font-weight: 500;\">Learn More<\/a>\r\n  <\/div>\r\n<\/div>\r\n<\/div>\n<p>Product | Affected Versions<\/p>\n<p>vLLM | 0.6.5 to 0.8.4<\/p>\n<p><strong>How the Exploit Works<\/strong><\/p>\n<p>The <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-48816-integer-overflow-vulnerability-in-hid-class-driver-leading-to-local-privilege-escalation\/\"  data-wpil-monitor-id=\"76729\">vulnerability arises from vLLM&#8217;s implementation of the `PyNcclPipe` class<\/a> to establish a P2P communication domain for data transmission between distributed nodes. The `TCPStore` interface, part of the PyTorch framework, was intended to listen only on the IP address specified by the `&#8211;kv-ip` CLI parameter, thus limiting exposure to a private, <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-52950-unauthorized-access-exploitation-in-juniper-networks-security-director\/\"  data-wpil-monitor-id=\"76730\">secured network<\/a>. However, <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-28389-critical-security-vulnerability-in-openc3-cosmos-v6-0-0-due-to-weak-password-requirements\/\"  data-wpil-monitor-id=\"61584\">due to a security<\/a> oversight, the `TCPStore` interface listens on all interfaces, disregarding the provided IP address. This behavior <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2024-22190-critical-gitpython-vulnerability-exposes-windows-systems-to-potential-compromise\/\"  data-wpil-monitor-id=\"51333\">exposes the vLLM engine to potential<\/a> unauthorized access and exploitation over the network.<\/p>\n<p><strong>Conceptual Example Code<\/strong><\/p><div id=\"ameeb-706845627\" class=\"ameeb-content ameeb-entity-placement\"><div class=\"poptin-embedded\" data-id=\"f6b387694f681\"><\/div>\r\n\r\n\r\n\r\n\r\n\r\n<\/div>\n<p>Here&#8217;s a conceptual example of an <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-4827-critical-buffer-overflow-vulnerability-in-totolink-http-post-request-handler\/\"  data-wpil-monitor-id=\"51334\">HTTP request that could exploit this vulnerability<\/a>:<\/p>\n<pre><code class=\"\" data-line=\"\">POST \/vLLM\/execute HTTP\/1.1\nHost: vulnerable.example.com\nContent-Type: application\/json\n{\n&quot;command&quot;: &quot;dump_kvcache&quot;,\n&quot;kvstore&quot;: &quot;PyNcclPipe&quot;\n}<\/code><\/pre>\n<p>In this conceptual example, an attacker sends a malicious `POST` <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-4829-critical-buffer-overflow-vulnerability-in-totolink-http-post-request-handler\/\"  data-wpil-monitor-id=\"52217\">request<\/a> to the vLLM engine&#8217;s execution endpoint. The `&#8221;dump_kvcache&#8221;` command could force the vLLM engine to dump the contents of the KV cache, <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2024-0582-a-potentially-dangerous-memory-leak-vulnerability-in-linux-kernel-s-io-uring-functionality\/\"  data-wpil-monitor-id=\"51988\">potentially leaking<\/a> sensitive data over the network.<\/p>\n<p><strong>Mitigation Steps<\/strong><\/p>\n<p>This <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-40906-critical-vulnerability-in-bson-xs-versions-0-8-4-and-earlier\/\"  data-wpil-monitor-id=\"50660\">vulnerability has been patched in vLLM version<\/a> 0.8.5, which now limits the `TCPStore` socket to the private interface as configured. All users are advised to update to this version or later to mitigate the risks posed by CVE-2025-47277.<br \/>\nIn situations where immediate patching is not feasible, <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-31100-unrestricted-file-upload-leads-to-web-shell-deployment-in-mojoomla-school-management\/\"  data-wpil-monitor-id=\"84743\">deploying a Web<\/a> Application Firewall (WAF) or Intrusion Detection System (IDS) could serve as a temporary mitigation measure. These systems can monitor and control incoming network traffic based on predefined security policies, <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2024-52880-critical-vulnerability-in-insyde-insydeh2o-kernels-potentially-leading-to-system-compromise\/\"  data-wpil-monitor-id=\"51426\">potentially preventing exploitation of this vulnerability<\/a>.<br \/>\nDespite these measures, it is imperative to apply the vendor patch as soon as possible to fully <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2024-49842-critical-memory-corruption-vulnerability-in-protected-vm-address-space\/\"  data-wpil-monitor-id=\"58863\">address the vulnerability<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Overview The vulnerability CVE-2025-47277 is a highly critical security flaw found in the vLLM, an inference and serving engine for large language models. Specifically, the vulnerability affects the `PyNcclPipe` KV cache transfer integration with the V0 engine in versions 0.6.5 through 0.8.4. The exploitation of this vulnerability could potentially lead to system compromise or data [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"footnotes":""},"categories":[1],"tags":[],"vendor":[],"product":[],"attack_vector":[],"asset_type":[],"severity":[],"exploit_status":[],"class_list":["post-44926","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/44926","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/comments?post=44926"}],"version-history":[{"count":11,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/44926\/revisions"}],"predecessor-version":[{"id":77528,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/44926\/revisions\/77528"}],"wp:attachment":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/media?parent=44926"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/categories?post=44926"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/tags?post=44926"},{"taxonomy":"vendor","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/vendor?post=44926"},{"taxonomy":"product","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/product?post=44926"},{"taxonomy":"attack_vector","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/attack_vector?post=44926"},{"taxonomy":"asset_type","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/asset_type?post=44926"},{"taxonomy":"severity","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/severity?post=44926"},{"taxonomy":"exploit_status","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/exploit_status?post=44926"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}