{"answers":{"affected":"","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-12234 exists.","fix":"No fix has been published for CVE-2026-12234 yet. Limit exposure of the affected software until one is available.","what":"CVE-2026-12234 is a high-severity vulnerability in zephyrproject zephyr, published on 12 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-12234 and fix it if it is affected.\n\nWhat it is: CVE-2026-12234 is a high-severity vulnerability in zephyrproject zephyr, published on 12 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-12234 exists.\n\nAffected product: zephyrproject zephyr. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-12234/ (Markdown: https://insights.sbomify.com/CVE-2026-12234/index.md)","id":"CVE-2026-12234","markdown":"https://insights.sbomify.com/CVE-2026-12234/index.md","name":"CVE-2026-12234","record":{"aliases":["GHSA-fcp3-vrr2-xfjv"],"analysis":{"component_type":"operating_system","fix_type":"patch","impacts":["privilege_escalation","denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":true,"product_category":"Zephyr RTOS","requires_auth":"low_privilege","summary":"A race condition in Zephyr RTOS socket verifiers allows local attackers to corrupt kernel memory, leading to privilege escalation or denial of service.","user_interaction":"not_required","vuln_class":"race_condition"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"zephyr","cpe":[],"cvss":{"score":7.8,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-367","name":"Time-of-check Time-of-use (TOCTOU) Race Condition"}],"description":"The userspace syscall verifiers z_vrfy_zsock_sendmsg() and z_vrfy_zsock_recvmsg() in subsys/net/lib/sockets/sockets.c snapshot the caller-supplied struct net_msghdr into a kernel-side copy with k_usermode_from_copy(), but then re-read the still-live user struct for subsequent decisions. The kernel iovec shadow buffer is sized from one read of msg-\u003emsg_iovlen, while the population loop is bounded by a second, live read of the same field.\n\nBecause msg points into ordinary user memory, a cooperating second thread in the same memory domain can inflate msg-\u003emsg_iovlen in the window between the sizing read and the loop test (a classic double-fetch / TOCTOU). The population loop then iterates past the number of net_iovec slots actually allocated, writing attacker-influenced iov_base/iov_len values beyond the end of the kernel-heap shadow buffer. The recvmsg verifier has the same defect on both its inbound and result write-back loops.\n\nThe code is reachable from an unprivileged user thread whenever CONFIG_USERSPACE is enabled and the zsock_sendmsg/zsock_recvmsg syscalls are available. A successful race corrupts kernel-managed heap memory across the user-to-kernel privilege boundary, yielding a local privilege-escalation primitive or, at minimum, a kernel-fault denial of service. The fix copies the header once and derives every size, bound, and gate from the snapshot, copying each iovec entry atomically so its base and length can no longer be raced apart.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":false,"headline":"TOCTOU double-fetch in `zsock_sendmsg`/`recvmsg` userspace verifiers allows kernel-heap out-of-bounds write","id":"CVE-2026-12234","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"race_condition","year":"2026"},"n_packages":0,"n_references":2,"next":{"headline":"Out-of-bounds write in Xtensa llext PLT relocation from malformed ELF (CWE-787)","id":"CVE-2026-12235"},"packages":[],"prev":{"headline":"Uninitialized mutex in TLS trusted-credential backend causes kernel NULL-deref DoS under contention","id":"CVE-2026-12233"},"products":["zephyr"],"published":"2026-08-12","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"poc","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-08-12","vendors":["zephyrproject"]},"summary":"A race condition in Zephyr RTOS socket verifiers allows local attackers to corrupt kernel memory, leading to privilege escalation or denial of service.","url":"https://insights.sbomify.com/CVE-2026-12234/"}