{ "document": { "category": "csaf_base", "csaf_version": "2.0", "distribution": { "tlp": { "label": "WHITE" } }, "lang": "en", "notes": [ { "category": "legal_disclaimer", "text": "The Netherlands Cyber Security Center (henceforth: NCSC-NL) maintains this portal to enhance access to its information and vulnerabilities. The use of this information is subject to the following terms and conditions:\n\nThe vulnerabilities disclosed in this portal are gathered by NCSC-NL from a variety of open sources, which the user can retrieve from other platforms. NCSC-NL makes every reasonable effort to ensure that the content of this portal is kept up to date, and that it is accurate and complete. Nevertheless, NCSC-NL cannot entirely rule out the possibility of errors, and therefore cannot give any warranty in respect of its completeness, accuracy or real-time keeping up-to-date. NCSC-NL does not control nor guarantee the accuracy, relevance, timeliness or completeness of information obtained from these external sources. The vulnerabilities disclosed in this portal are intended solely for the convenience of professional parties to take appropriate measures to manage the risks posed to the cybersecurity. No rights can be derived from the information provided therein.\n\nNCSC-NL and the Kingdom of the Netherlands assume no legal liability or responsibility for any damage resulting from either the use or inability of use of the vulnerabilities disclosed in this portal. This includes damage resulting from the inaccuracy of incompleteness of the information contained in it.\nThe information on this page is subject to Dutch law. All disputes related to or arising from the use of this portal regarding the disclosure of vulnerabilities will be submitted to the competent court in The Hague. This choice of means also applies to the court in summary proceedings." } ], "publisher": { "category": "coordinator", "contact_details": "cert@ncsc.nl", "name": "National Cyber Security Centre", "namespace": "https://www.ncsc.nl/" }, "title": "CVE-2026-10655", "tracking": { "current_release_date": "2026-09-06T03:20:57.422782Z", "generator": { "date": "2026-02-17T15:00:00Z", "engine": { "name": "V.E.L.M.A", "version": "1.7" } }, "id": "CVE-2026-10655", "initial_release_date": "2026-06-30T16:59:21.119610Z", "revision_history": [ { "date": "2026-06-30T16:59:21.119610Z", "number": "1", "summary": "CVE created.| Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products connected (1).| References created (2).| CWES updated (1)." }, { "date": "2026-06-30T16:59:23.283541Z", "number": "2", "summary": "NCSC Score created." }, { "date": "2026-06-30T17:40:28.779387Z", "number": "3", "summary": "Unknown change." }, { "date": "2026-06-30T17:49:02.627423Z", "number": "4", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (2).| CWES updated (1)." }, { "date": "2026-06-30T17:49:05.395828Z", "number": "5", "summary": "NCSC Score updated." }, { "date": "2026-07-01T03:27:10.044822Z", "number": "6", "summary": "NCSC Score updated." }, { "date": "2026-07-01T14:45:33.749296Z", "number": "7", "summary": "Source connected.| CVE status created. (valid)| EPSS created." }, { "date": "2026-07-01T14:45:37.781774Z", "number": "8", "summary": "NCSC Score updated." }, { "date": "2026-07-06T20:28:23.392923Z", "number": "9", "summary": "Products created (1).| Product Identifiers created (1).| Exploits created (1)." }, { "date": "2026-07-06T20:28:25.167568Z", "number": "10", "summary": "NCSC Score updated." }, { "date": "2026-07-10T15:41:44.884012Z", "number": "11", "summary": "Source connected.| CVE status created. (valid)| EPSS created." }, { "date": "2026-07-10T15:41:46.475118Z", "number": "12", "summary": "NCSC Score updated." }, { "date": "2026-07-12T18:45:23.144206Z", "number": "13", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products connected (8).| References created (4).| CWES updated (1)." }, { "date": "2026-07-12T18:45:33.795567Z", "number": "14", "summary": "NCSC Score updated." }, { "date": "2026-08-11T15:11:53.048740Z", "number": "15", "summary": "Source connected.| CVE status created. (valid)| EPSS created." }, { "date": "2026-08-11T15:13:11.107677Z", "number": "16", "summary": "NCSC Score updated." }, { "date": "2026-09-02T10:45:46.159587Z", "number": "17", "summary": "EPSS updated." }, { "date": "2026-09-02T23:35:01.020436Z", "number": "18", "summary": "NCSC Score updated." }, { "date": "2026-09-03T14:38:16.278485Z", "number": "19", "summary": "EPSS updated." }, { "date": "2026-09-03T19:01:41.651706Z", "number": "20", "summary": "EPSS updated." }, { "date": "2026-09-04T15:47:42.079873Z", "number": "21", "summary": "EPSS updated." }, { "date": "2026-09-04T15:47:43.009906Z", "number": "22", "summary": "NCSC Score updated." }, { "date": "2026-09-05T15:45:34.513042Z", "number": "23", "summary": "EPSS updated." } ], "status": "interim", "version": "23" } }, "product_tree": { "branches": [ { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:semver/4.2.0|<4.5.0", "product": { "name": "vers:semver/4.2.0|<4.5.0", "product_id": "CSAFPID-8467526" } }, { "category": "product_version_range", "name": "vers:unknown/>=4.2.0|<=4.4.1", "product": { "name": "vers:unknown/>=4.2.0|<=4.4.1", "product_id": "CSAFPID-8537799", "product_identification_helper": { "cpe": "cpe:2.3:o:zephyrproject:zephyr:*:*:*:*:*:*:*:*" } } } ], "category": "product_name", "name": "Zephyr" } ], "category": "vendor", "name": "Zephyrproject" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:unknown/v4.2.0", "product": { "name": "vers:unknown/v4.2.0", "product_id": "CSAFPID-8566770" } }, { "category": "product_version_range", "name": "vers:unknown/v4.3.0", "product": { "name": "vers:unknown/v4.3.0", "product_id": "CSAFPID-8570147" } }, { "category": "product_version_range", "name": "vers:unknown/v4.3.0-rc1", "product": { "name": "vers:unknown/v4.3.0-rc1", "product_id": "CSAFPID-8570150" } }, { "category": "product_version_range", "name": "vers:unknown/v4.3.0-rc2", "product": { "name": "vers:unknown/v4.3.0-rc2", "product_id": "CSAFPID-8570149" } }, { "category": "product_version_range", "name": "vers:unknown/v4.3.0-rc3", "product": { "name": "vers:unknown/v4.3.0-rc3", "product_id": "CSAFPID-8570148" } }, { "category": "product_version_range", "name": "vers:unknown/v4.4.0-rc1", "product": { "name": "vers:unknown/v4.4.0-rc1", "product_id": "CSAFPID-8570146" } }, { "category": "product_version_range", "name": "vers:unknown/v4.4.0-rc2", "product": { "name": "vers:unknown/v4.4.0-rc2", "product_id": "CSAFPID-8570145" } }, { "category": "product_version_range", "name": "vers:unknown/v4.4.0-rc3", "product": { "name": "vers:unknown/v4.4.0-rc3", "product_id": "CSAFPID-8570144" } } ], "category": "product_name", "name": "zephyr" } ], "category": "vendor", "name": "zephyrproject-rtos" } ] }, "vulnerabilities": [ { "cve": "CVE-2026-10655", "cwe": { "id": "CWE-416", "name": "Use After Free" }, "notes": [ { "category": "description", "text": "The asynchronous SNTP client in Zephyr (subsys/net/lib/sntp/sntp.c, sntp_close_async) closed the UDP socket file descriptor directly from the calling thread immediately after detaching it from the network socket service, without synchronizing with the socket-service poll thread.\n\nThe socket service thread polls each socket via zvfs_poll, which (in zsock_poll_prepare_ctx) registers a k_poll_event pointing into the socket's net_context (&ctx->recv_q) and then blocks in k_poll without holding a reference or lock. net_context objects are allocated from a fixed pool (contexts[CONFIG_NET_MAX_CONTEXTS]) and reused after close.\n\nWhen sntp_close_async is invoked from a different thread than the poll thread (in the in-tree consumer subsys/net/lib/config/init_clock_sntp.c, the SNTP timeout handler runs on the system workqueue while the socket service thread is blocked in poll on the same fd), the close frees and may reuse the net_context while the poll thread still has a poller node linked into the freed object, resulting in a use-after-free / object confusion of kernel poll structures.\n\nThe SNTP timeout path is the normal no-response failure mode, so a network peer or off-path attacker who drops or delays the SNTP/NTP response can drive the racing close repeatedly (and periodically with NET_CONFIG_SNTP_INIT_RESYNC). The most likely consequence is a crash of the networking thread (denial of service), with potential memory corruption when the freed context slot is reallocated.\n\nThe fix defers the close to the socket service thread itself via net_socket_service_close (NET_SOCKET_SERVICE_CLOSE_SOCKETS), so the same thread that polls performs the close, eliminating the race. Affected releases: v4.2.0 through v4.4.0.", "title": "cveprojectv5 - https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/10xxx/CVE-2026-10655.json" }, { "category": "description", "text": "The asynchronous SNTP client in Zephyr (subsys/net/lib/sntp/sntp.c, sntp_close_async) closed the UDP socket file descriptor directly from the calling thread immediately after detaching it from the network socket service, without synchronizing with the socket-service poll thread.\n\nThe socket service thread polls each socket via zvfs_poll, which (in zsock_poll_prepare_ctx) registers a k_poll_event pointing into the socket's net_context (&ctx->recv_q) and then blocks in k_poll without holding a reference or lock. net_context objects are allocated from a fixed pool (contexts[CONFIG_NET_MAX_CONTEXTS]) and reused after close.\n\nWhen sntp_close_async is invoked from a different thread than the poll thread (in the in-tree consumer subsys/net/lib/config/init_clock_sntp.c, the SNTP timeout handler runs on the system workqueue while the socket service thread is blocked in poll on the same fd), the close frees and may reuse the net_context while the poll thread still has a poller node linked into the freed object, resulting in a use-after-free / object confusion of kernel poll structures.\n\nThe SNTP timeout path is the normal no-response failure mode, so a network peer or off-path attacker who drops or delays the SNTP/NTP response can drive the racing close repeatedly (and periodically with NET_CONFIG_SNTP_INIT_RESYNC). The most likely consequence is a crash of the networking thread (denial of service), with potential memory corruption when the freed context slot is reallocated.\n\nThe fix defers the close to the socket service thread itself via net_socket_service_close (NET_SOCKET_SERVICE_CLOSE_SOCKETS), so the same thread that polls performs the close, eliminating the race. Affected releases: v4.2.0 through v4.4.0.", "title": "nvd - https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-10655" }, { "category": "description", "text": "The asynchronous SNTP client in Zephyr (subsys/net/lib/sntp/sntp.c, sntp_close_async) closed the UDP socket file descriptor directly from the calling thread immediately after detaching it from the network socket service, without synchronizing with the socket-service poll thread.\n\nThe socket service thread polls each socket via zvfs_poll, which (in zsock_poll_prepare_ctx) registers a k_poll_event pointing into the socket's net_context (&ctx->recv_q) and then blocks in k_poll without holding a reference or lock. net_context objects are allocated from a fixed pool (contexts[CONFIG_NET_MAX_CONTEXTS]) and reused after close.\n\nWhen sntp_close_async is invoked from a different thread than the poll thread (in the in-tree consumer subsys/net/lib/config/init_clock_sntp.c, the SNTP timeout handler runs on the system workqueue while the socket service thread is blocked in poll on the same fd), the close frees and may reuse the net_context while the poll thread still has a poller node linked into the freed object, resulting in a use-after-free / object confusion of kernel poll structures.\n\nThe SNTP timeout path is the normal no-response failure mode, so a network peer or off-path attacker who drops or delays the SNTP/NTP response can drive the racing close repeatedly (and periodically with NET_CONFIG_SNTP_INIT_RESYNC). The most likely consequence is a crash of the networking thread (denial of service), with potential memory corruption when the freed context slot is reallocated.\n\nThe fix defers the close to the socket service thread itself via net_socket_service_close (NET_SOCKET_SERVICE_CLOSE_SOCKETS), so the same thread that polls performs the close, eliminating the race. Affected releases: v4.2.0 through v4.4.0.", "title": "osv - https://www.googleapis.com/download/storage/v1/b/osv-vulnerabilities/o/GIT%2FCVE-2026-10655.json?alt=media" }, { "category": "other", "text": "0.0038", "title": "EPSS" }, { "category": "other", "text": "4.1", "title": "NCSC Score" }, { "category": "other", "text": "Is related to CWE-416 (Use After Free)", "title": "NCSC Score top increasing factors" }, { "category": "other", "text": "Is related to (a version of) an uncommon product, Exploit code publicly available, Is related to an uncommon product vendor, There is exploit data available from source Nvd, There is cwe data available from source Nvd", "title": "NCSC Score top decreasing factors" } ], "product_status": { "known_affected": [ "CSAFPID-8467526", "CSAFPID-8537799", "CSAFPID-8566770", "CSAFPID-8570144", "CSAFPID-8570145", "CSAFPID-8570146", "CSAFPID-8570147", "CSAFPID-8570148", "CSAFPID-8570149", "CSAFPID-8570150" ] }, "references": [ { "category": "external", "summary": "Source - first", "url": "https://api.first.org/data/v1/epss" }, { "category": "external", "summary": "Source - cveprojectv5", "url": "https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/10xxx/CVE-2026-10655.json" }, { "category": "external", "summary": "Source - nvd", "url": "https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-10655" }, { "category": "external", "summary": "Source - osv", "url": "https://www.googleapis.com/download/storage/v1/b/osv-vulnerabilities/o/GIT%2FCVE-2026-10655.json?alt=media" }, { "category": "external", "summary": "Source - ncscclear", "url": "https://vulnerabilities.ncsc.nl/manual/CVE-2026-10655" }, { "category": "external", "summary": "Reference - cveprojectv5; nvd; osv", "url": "https://github.com/zephyrproject-rtos/zephyr/commit/ef47bdf328b4206ac3b3922ec09184f7a6f7412a" }, { "category": "external", "summary": "Reference - cveprojectv5; nvd; osv", "url": "https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-34wr-cg29-c4mw" }, { "category": "external", "summary": "Reference - osv", "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/10xxx/CVE-2026-10655.json" }, { "category": "external", "summary": "Reference - osv", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-10655" } ], "scores": [ { "cvss_v3": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H", "baseScore": 6.5, "baseSeverity": "MEDIUM" }, "products": [ "CSAFPID-8467526", "CSAFPID-8537799", "CSAFPID-8566770", "CSAFPID-8570144", "CSAFPID-8570145", "CSAFPID-8570146", "CSAFPID-8570147", "CSAFPID-8570148", "CSAFPID-8570149", "CSAFPID-8570150" ] } ], "title": "CVE-2026-10655" } ] }