{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-52947","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-06-09T07:44:35.371Z","datePublished":"2026-06-24T16:26:05.062Z","dateUpdated":"2026-06-28T06:37:05.590Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-06-28T06:37:05.590Z"},"descriptions":[{"lang":"en","value":"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.)"}],"metrics":[{"cvssV3_1":{"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"}}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/qrtr/af_qrtr.c"],"versions":[{"version":"bdabad3e363d825ddf9679dd431cca0b2c30f881","lessThan":"2aa4c12723fe432e623462a3be42a197a128722b","status":"affected","versionType":"git"},{"version":"bdabad3e363d825ddf9679dd431cca0b2c30f881","lessThan":"03bfa95e452e2b6ccd76a332060ae4feaf5ad84d","status":"affected","versionType":"git"},{"version":"bdabad3e363d825ddf9679dd431cca0b2c30f881","lessThan":"474293d90880622fde9d2430fb0165767090f7b3","status":"affected","versionType":"git"},{"version":"bdabad3e363d825ddf9679dd431cca0b2c30f881","lessThan":"2047c2aa0963bb2872fd722300a15bcb441a4c00","status":"affected","versionType":"git"},{"version":"bdabad3e363d825ddf9679dd431cca0b2c30f881","lessThan":"7de2d447072be3b1a76793f034432338fc9c494b","status":"affected","versionType":"git"},{"version":"bdabad3e363d825ddf9679dd431cca0b2c30f881","lessThan":"ab269990ed58143a92a263be1bee626d82ac03da","status":"affected","versionType":"git"},{"version":"bdabad3e363d825ddf9679dd431cca0b2c30f881","lessThan":"3b20ec8f31e8a6a6782243f473b0abd3463621df","status":"affected","versionType":"git"},{"version":"bdabad3e363d825ddf9679dd431cca0b2c30f881","lessThan":"a2171131ecda1ed61a594a1eb715e75fdad0fef5","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/qrtr/af_qrtr.c"],"versions":[{"version":"4.7","status":"affected"},{"version":"0","lessThan":"4.7","status":"unaffected","versionType":"semver"},{"version":"5.10.259","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.210","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.176","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.143","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.94","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.36","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.0.13","lessThanOrEqual":"7.0.*","status":"unaffected","versionType":"semver"},{"version":"7.1","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.7","versionEndExcluding":"5.10.259"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.7","versionEndExcluding":"5.15.210"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.7","versionEndExcluding":"6.1.176"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.7","versionEndExcluding":"6.6.143"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.7","versionEndExcluding":"6.12.94"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.7","versionEndExcluding":"6.18.36"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.7","versionEndExcluding":"7.0.13"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.7","versionEndExcluding":"7.1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/2aa4c12723fe432e623462a3be42a197a128722b"},{"url":"https://git.kernel.org/stable/c/03bfa95e452e2b6ccd76a332060ae4feaf5ad84d"},{"url":"https://git.kernel.org/stable/c/474293d90880622fde9d2430fb0165767090f7b3"},{"url":"https://git.kernel.org/stable/c/2047c2aa0963bb2872fd722300a15bcb441a4c00"},{"url":"https://git.kernel.org/stable/c/7de2d447072be3b1a76793f034432338fc9c494b"},{"url":"https://git.kernel.org/stable/c/ab269990ed58143a92a263be1bee626d82ac03da"},{"url":"https://git.kernel.org/stable/c/3b20ec8f31e8a6a6782243f473b0abd3463621df"},{"url":"https://git.kernel.org/stable/c/a2171131ecda1ed61a594a1eb715e75fdad0fef5"}],"title":"net: qrtr: fix refcount saturation and potential UAF in qrtr_port_remove","x_generator":{"engine":"bippy-1.2.0"}}}}