{"id":"CVE-2026-52947","revision":null,"records":[{"revision":"cd2393c445d04fe68989286c3d24313b","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-52947","aliases":[],"title":"net: qrtr: fix refcount saturation and potential UAF in qrtr_port_remove","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: qrtr: fix refcount saturation and potential UAF in qrtr_port_remove\n\nIn qrtr_port_remove(), the socket reference count is decremented via\n__sock_put() before the port is removed from the qrtr_ports XArray and\nbefore the RCU grace period elapses.\n\nThis breaks the fundamental RCU update paradigm. It exposes a race\nwindow where a concurrent RCU reader (such as qrtr_reset_ports() or\nqrtr_port_lookup()) can obtain a pointer to the socket from the XArray,\nand attempt to call sock_hold() on a socket whose reference count has\nalready dropped to zero.\n\nThis exact race condition was hit during syzkaller fuzzing, leading to\nthe following refcount saturation warning and a potential Use-After-Free:\n\n  refcount_t: saturated; leaking memory.\n  WARNING: CPU: 3 PID: 1273 at lib/refcount.c:22 refcount_warn_saturate+0xae/0x1d0\n  Modules linked in: qrtr(+) bochs drm_shmem_helper ...\n  Call Trace:\n   <TASK>\n   qrtr_reset_ports net/qrtr/af_qrtr.c:768 [inline] [qrtr]\n   __qrtr_bind.isra.0+0x48b/0x570 net/qrtr/af_qrtr.c:805 [qrtr]\n   qrtr_bind+0x17d/0x210 net/qrtr/af_qrtr.c:901 [qrtr]\n   kernel_bind+0xe4/0x120 net/socket.c:3592\n   qrtr_ns_init+0x1a6/0x380 net/qrtr/ns.c:715 [qrtr]\n   qrtr_proto_init+0x3b/0xff0 net/qrtr/af_qrtr.c:169 [qrtr]\n   do_one_initcall+0xf5/0x5e0 init/main.c:1283\n   ...\n   </TASK>\n\nFix this by deferring the reference count decrement until after the\nxa_erase() and the synchronize_rcu() complete.\n\n(Note: The v1 of this patch incorrectly replaced __sock_put() with\nsock_put(). As Simon Horman pointed out, the callers of qrtr_port_remove()\nstill hold a reference to the socket, so freeing the socket memory here\nwould lead to a subsequent UAF in the caller. Thus, the __sock_put() is\nkept, but only repositioned to close the RCU race.)","state":0,"publishedAt":"2026-06-24T16:26:05.062+00:00","modifiedAt":"2026-10-19T19:47:09.2+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/qrtr/af_qrtr.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"bdabad3e363d825ddf9679dd431cca0b2c30f881\",\n                            \"lessThan\": \"2aa4c12723fe432e623462a3be42a197a128722b\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"bdabad3e363d825ddf9679dd431cca0b2c30f881\",\n                            \"lessThan\": \"03bfa95e452e2b6ccd76a332060ae4feaf5ad84d\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"bdabad3e363d825ddf9679dd431cca0b2c30f881\",\n                            \"lessThan\": \"474293d90880622fde9d2430fb0165767090f7b3\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"bdabad3e363d825ddf9679dd431cca0b2c30f881\",\n                            \"lessThan\": \"2047c2aa0963bb2872fd722300a15bcb441a4c00\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"bdabad3e363d825ddf9679dd431cca0b2c30f881\",\n                            \"lessThan\": \"7de2d447072be3b1a76793f034432338fc9c494b\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"bdabad3e363d825ddf9679dd431cca0b2c30f881\",\n                            \"lessThan\": \"ab269990ed58143a92a263be1bee626d82ac03da\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"bdabad3e363d825ddf9679dd431cca0b2c30f881\",\n                            \"lessThan\": \"3b20ec8f31e8a6a6782243f473b0abd3463621df\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"bdabad3e363d825ddf9679dd431cca0b2c30f881\",\n                            \"lessThan\": \"a2171131ecda1ed61a594a1eb715e75fdad0fef5\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/qrtr/af_qrtr.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"4.7\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"4.7\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.259\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.210\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.176\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.143\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.94\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.36\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.0.13\",\n                            \"lessThanOrEqual\": \"7.0.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.1\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/2aa4c12723fe432e623462a3be42a197a128722b","https://git.kernel.org/stable/c/03bfa95e452e2b6ccd76a332060ae4feaf5ad84d","https://git.kernel.org/stable/c/474293d90880622fde9d2430fb0165767090f7b3","https://git.kernel.org/stable/c/2047c2aa0963bb2872fd722300a15bcb441a4c00","https://git.kernel.org/stable/c/7de2d447072be3b1a76793f034432338fc9c494b","https://git.kernel.org/stable/c/ab269990ed58143a92a263be1bee626d82ac03da","https://git.kernel.org/stable/c/3b20ec8f31e8a6a6782243f473b0abd3463621df","https://git.kernel.org/stable/c/a2171131ecda1ed61a594a1eb715e75fdad0fef5"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-52947","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-52947","identifiers":["CVE-2026-52947"]},"retained":false,"historicalAffected":[]}],"coverage":[{"source":"cisa-kev:global","scope":"Complete CISA KEV catalog; all 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Not a global EPSS backfill.","generation":"2026-11-08T19:47:20.1649891+00:00","complete":true,"records":1096,"lastAttemptAt":"2026-11-08T19:47:20.1649891+00:00","lastSuccessAt":"2026-11-08T19:47:20.3951142+00:00","error":null,"lastVerifiedAt":"2026-11-08T19:47:20.3951146+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"nvd","scope":"Rolling NVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global NVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-3b79c659b4ac42b2801e63ff6ff3a882","complete":false,"records":13666,"lastAttemptAt":"2026-11-08T19:47:46.1695591+00:00","lastSuccessAt":"2026-11-08T19:47:46.166+00:00","error":null,"lastVerifiedAt":"2026-11-08T19:47:46.166+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13206,"expectedIdentifiers":13706,"failedIdentifiers":0},{"source":"osv:Go","scope":"Complete OSV Go ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"go-980593e6977a6d1b4fb1eed5a1ffe88a468736f89f0a06f710924ad59132c023","complete":true,"records":9914,"lastAttemptAt":"2026-11-08T19:47:20.0165357+00:00","lastSuccessAt":"2026-11-08T11:07:07.068788+00:00","error":null,"lastVerifiedAt":"2026-11-08T19:47:20.0165357+00:00","snapshotPublishedAt":"2026-11-08T11:02:46+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:NuGet","scope":"Complete OSV NuGet ecosystem archive, including GitHub Advisory Database records; NuGet version matching only","generation":"nuget-fde804134ecdda0ddd5ff5c26ee1fff5a6fa659311f7ef2e51c6ad54964db0e2","complete":true,"records":1971,"lastAttemptAt":"2026-11-08T19:47:19.7560084+00:00","lastSuccessAt":"2026-11-06T19:03:17.0399903+00:00","error":null,"lastVerifiedAt":"2026-11-08T19:47:19.7560084+00:00","snapshotPublishedAt":"2026-11-06T18:17:57+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:crates.io","scope":"Complete OSV crates.io ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"crates.io-964c14035e6f0f6478b2870fad6a7ef9f6045876d4a12af2c2e514521e54b6af","complete":true,"records":3055,"lastAttemptAt":"2026-11-08T19:47:20.1181272+00:00","lastSuccessAt":"2026-11-08T11:07:12.1927025+00:00","error":null,"lastVerifiedAt":"2026-11-08T19:47:20.1181272+00:00","snapshotPublishedAt":"2026-11-08T11:02:46+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:npm","scope":"Complete OSV npm ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"npm-f8647d7ba64b1ba0dfdc7130944766d5b36d5b77d18fff0c79e651a4cff3c2b9","complete":true,"records":231293,"lastAttemptAt":"2026-11-08T19:47:19.9161497+00:00","lastSuccessAt":"2026-11-08T11:06:56.2918717+00:00","error":null,"lastVerifiedAt":"2026-11-08T19:47:19.9161497+00:00","snapshotPublishedAt":"2026-11-08T11:02:50+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null}]}