{"id":"CVE-2026-90088","state":"PUBLISHED","title":"Bluetooth: RFCOMM: Validate MTU in rfcomm_apply_pn() to prevent infinite loop","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: RFCOMM: Validate MTU in rfcomm_apply_pn() to prevent infinite loop\n\nrfcomm_apply_pn() accepts the MTU value from a remote PN (Parameter\nNegotiation) frame without checking for zero. When the remote peer\nsends an MTU of zero, d->mtu is set to 0. This causes the sendmsg\npath to enter an infinite loop when fragmenting data, as each fragment\nhas size == min_t(size_t, len, 0) == 0, so the remaining length never\ndecreases. The infinite allocation of zero-length skbs exhausts all\nsystem memory.\n\nFix by clamping d->mtu to RFCOMM_DEFAULT_MTU when the negotiated\nvalue is zero, consistent with the initial value assigned in\nrfcomm_dlc_alloc().","publishedAt":"2026-09-17T16:06:03.527Z","updatedAt":"2026-10-19T08:57:45.766Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"e7c0aa45ae6c5a338661b23812bfcdef50bf3e96","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"cbc2962da99b6b89345267d3aa74b4b573340548","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"9b2e5f1928c99224345a9ed8c5dae5fc74964d6d","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"fc4851ff8dfb505e9a19efcc286712132bbd178d","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"f561e44261344adadf9d6a6dff31e3af9776d5c6","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"aeee917a4878af95f0c63e18c5f22eaf6299c7b8","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"3988cbb1be501dbff909a2ee024670e3c955a66d","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"44c98fd082eafd49d55a8a4077ff488175b2fe24","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/bluetooth/rfcomm/core.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.12","versionType":"semver"},{"version":"5.10.270","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.221","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.52","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.6","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/bluetooth/rfcomm/core.c"]}],"references":["https://git.kernel.org/stable/c/e7c0aa45ae6c5a338661b23812bfcdef50bf3e96","https://git.kernel.org/stable/c/cbc2962da99b6b89345267d3aa74b4b573340548","https://git.kernel.org/stable/c/9b2e5f1928c99224345a9ed8c5dae5fc74964d6d","https://git.kernel.org/stable/c/fc4851ff8dfb505e9a19efcc286712132bbd178d","https://git.kernel.org/stable/c/f561e44261344adadf9d6a6dff31e3af9776d5c6","https://git.kernel.org/stable/c/aeee917a4878af95f0c63e18c5f22eaf6299c7b8","https://git.kernel.org/stable/c/3988cbb1be501dbff909a2ee024670e3c955a66d","https://git.kernel.org/stable/c/44c98fd082eafd49d55a8a4077ff488175b2fe24"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:34.582Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/90xxx/CVE-2026-90088.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-90088","state":"PUBLISHED","datePublished":"2026-09-17T16:06:03.527Z","dateUpdated":"2026-10-19T08:57:45.766Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-11T19:38:34.785Z"},"containers":{"cna":{"title":"Bluetooth: RFCOMM: Validate MTU in rfcomm_apply_pn() to prevent infinite loop","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: RFCOMM: Validate MTU in rfcomm_apply_pn() to prevent infinite loop\n\nrfcomm_apply_pn() accepts the MTU value from a remote PN (Parameter\nNegotiation) frame without checking for zero. When the remote peer\nsends an MTU of zero, d->mtu is set to 0. This causes the sendmsg\npath to enter an infinite loop when fragmenting data, as each fragment\nhas size == min_t(size_t, len, 0) == 0, so the remaining length never\ndecreases. The infinite allocation of zero-length skbs exhausts all\nsystem memory.\n\nFix by clamping d->mtu to RFCOMM_DEFAULT_MTU when the negotiated\nvalue is zero, consistent with the initial value assigned in\nrfcomm_dlc_alloc()."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"e7c0aa45ae6c5a338661b23812bfcdef50bf3e96","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"cbc2962da99b6b89345267d3aa74b4b573340548","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"9b2e5f1928c99224345a9ed8c5dae5fc74964d6d","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"fc4851ff8dfb505e9a19efcc286712132bbd178d","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"f561e44261344adadf9d6a6dff31e3af9776d5c6","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"aeee917a4878af95f0c63e18c5f22eaf6299c7b8","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"3988cbb1be501dbff909a2ee024670e3c955a66d","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"44c98fd082eafd49d55a8a4077ff488175b2fe24","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/bluetooth/rfcomm/core.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.12","versionType":"semver"},{"version":"5.10.270","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.221","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.52","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.6","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/bluetooth/rfcomm/core.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/e7c0aa45ae6c5a338661b23812bfcdef50bf3e96"},{"url":"https://git.kernel.org/stable/c/cbc2962da99b6b89345267d3aa74b4b573340548"},{"url":"https://git.kernel.org/stable/c/9b2e5f1928c99224345a9ed8c5dae5fc74964d6d"},{"url":"https://git.kernel.org/stable/c/fc4851ff8dfb505e9a19efcc286712132bbd178d"},{"url":"https://git.kernel.org/stable/c/f561e44261344adadf9d6a6dff31e3af9776d5c6"},{"url":"https://git.kernel.org/stable/c/aeee917a4878af95f0c63e18c5f22eaf6299c7b8"},{"url":"https://git.kernel.org/stable/c/3988cbb1be501dbff909a2ee024670e3c955a66d"},{"url":"https://git.kernel.org/stable/c/44c98fd082eafd49d55a8a4077ff488175b2fe24"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T08:57:45.766Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"5.10.270"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"5.15.221"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"6.1.188"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"6.6.157"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"6.12.110"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"6.18.52"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"7.2.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}