{"id":"CVE-2025-21689","state":"PUBLISHED","title":"USB: serial: quatech2: fix null-ptr-deref in qt2_process_read_urb()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nUSB: serial: quatech2: fix null-ptr-deref in qt2_process_read_urb()\n\nThis patch addresses a null-ptr-deref in qt2_process_read_urb() due to\nan incorrect bounds check in the following:\n\n       if (newport > serial->num_ports) {\n               dev_err(&port->dev,\n                       \"%s - port change to invalid port: %i\\n\",\n                       __func__, newport);\n               break;\n       }\n\nThe condition doesn't account for the valid range of the serial->port\nbuffer, which is from 0 to serial->num_ports - 1. When newport is equal\nto serial->num_ports, the assignment of \"port\" in the\nfollowing code is out-of-bounds and NULL:\n\n       serial_priv->current_port = newport;\n       port = serial->port[serial_priv->current_port];\n\nThe fix checks if newport is greater than or equal to serial->num_ports\nindicating it is out-of-bounds.","publishedAt":"2025-02-10T15:58:45.493Z","updatedAt":"2026-05-11T21:04:31.416Z","severity":{"score":5.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","source":"CISA-ADP"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"f7a33e608d9ae022b7f49307921627e34e9484ed","status":"affected","lessThan":"fa4c7472469d97c4707698b4c0e098f8cfc2bf22","versionType":"git"},{"version":"f7a33e608d9ae022b7f49307921627e34e9484ed","status":"affected","lessThan":"94770cf7c5124f0268d481886829dc2beecc4507","versionType":"git"},{"version":"f7a33e608d9ae022b7f49307921627e34e9484ed","status":"affected","lessThan":"6068dcff7f19e9fa6fa23ee03453ad6a40fa4efe","versionType":"git"},{"version":"f7a33e608d9ae022b7f49307921627e34e9484ed","status":"affected","lessThan":"4b9b41fabcd38990f69ef0cee9c631d954a2b530","versionType":"git"},{"version":"f7a33e608d9ae022b7f49307921627e34e9484ed","status":"affected","lessThan":"6377838560c03b36e1153a42ef727533def9b68f","versionType":"git"},{"version":"f7a33e608d9ae022b7f49307921627e34e9484ed","status":"affected","lessThan":"f371471708c7d997f763b0e70565026eb67cc470","versionType":"git"},{"version":"f7a33e608d9ae022b7f49307921627e34e9484ed","status":"affected","lessThan":"8542b33622571f54dfc2a267fce378b6e3840b8b","versionType":"git"},{"version":"f7a33e608d9ae022b7f49307921627e34e9484ed","status":"affected","lessThan":"575a5adf48b06a2980c9eeffedf699ed5534fade","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/usb/serial/quatech2.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.5","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.5","versionType":"semver"},{"version":"5.4.290","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.234","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.178","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.128","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.75","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.12","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.13.1","status":"unaffected","lessThanOrEqual":"6.13.*","versionType":"semver"},{"version":"6.14","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/usb/serial/quatech2.c"]}],"references":["https://git.kernel.org/stable/c/fa4c7472469d97c4707698b4c0e098f8cfc2bf22","https://git.kernel.org/stable/c/94770cf7c5124f0268d481886829dc2beecc4507","https://git.kernel.org/stable/c/6068dcff7f19e9fa6fa23ee03453ad6a40fa4efe","https://git.kernel.org/stable/c/4b9b41fabcd38990f69ef0cee9c631d954a2b530","https://git.kernel.org/stable/c/6377838560c03b36e1153a42ef727533def9b68f","https://git.kernel.org/stable/c/f371471708c7d997f763b0e70565026eb67cc470","https://git.kernel.org/stable/c/8542b33622571f54dfc2a267fce378b6e3840b8b","https://git.kernel.org/stable/c/575a5adf48b06a2980c9eeffedf699ed5534fade","https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html","https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html"],"weaknesses":["CWE-476"],"ingestedAt":"2026-10-29T20:08:39.238Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2025/21xxx/CVE-2025-21689.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-21689","state":"PUBLISHED","datePublished":"2025-02-10T15:58:45.493Z","dateUpdated":"2026-05-11T21:04:31.416Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2024-12-29T08:45:45.741Z"},"containers":{"cna":{"title":"USB: serial: quatech2: fix null-ptr-deref in qt2_process_read_urb()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nUSB: serial: quatech2: fix null-ptr-deref in qt2_process_read_urb()\n\nThis patch addresses a null-ptr-deref in qt2_process_read_urb() due to\nan incorrect bounds check in the following:\n\n       if (newport > serial->num_ports) {\n               dev_err(&port->dev,\n                       \"%s - port change to invalid port: %i\\n\",\n                       __func__, newport);\n               break;\n       }\n\nThe condition doesn't account for the valid range of the serial->port\nbuffer, which is from 0 to serial->num_ports - 1. When newport is equal\nto serial->num_ports, the assignment of \"port\" in the\nfollowing code is out-of-bounds and NULL:\n\n       serial_priv->current_port = newport;\n       port = serial->port[serial_priv->current_port];\n\nThe fix checks if newport is greater than or equal to serial->num_ports\nindicating it is out-of-bounds."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"f7a33e608d9ae022b7f49307921627e34e9484ed","status":"affected","lessThan":"fa4c7472469d97c4707698b4c0e098f8cfc2bf22","versionType":"git"},{"version":"f7a33e608d9ae022b7f49307921627e34e9484ed","status":"affected","lessThan":"94770cf7c5124f0268d481886829dc2beecc4507","versionType":"git"},{"version":"f7a33e608d9ae022b7f49307921627e34e9484ed","status":"affected","lessThan":"6068dcff7f19e9fa6fa23ee03453ad6a40fa4efe","versionType":"git"},{"version":"f7a33e608d9ae022b7f49307921627e34e9484ed","status":"affected","lessThan":"4b9b41fabcd38990f69ef0cee9c631d954a2b530","versionType":"git"},{"version":"f7a33e608d9ae022b7f49307921627e34e9484ed","status":"affected","lessThan":"6377838560c03b36e1153a42ef727533def9b68f","versionType":"git"},{"version":"f7a33e608d9ae022b7f49307921627e34e9484ed","status":"affected","lessThan":"f371471708c7d997f763b0e70565026eb67cc470","versionType":"git"},{"version":"f7a33e608d9ae022b7f49307921627e34e9484ed","status":"affected","lessThan":"8542b33622571f54dfc2a267fce378b6e3840b8b","versionType":"git"},{"version":"f7a33e608d9ae022b7f49307921627e34e9484ed","status":"affected","lessThan":"575a5adf48b06a2980c9eeffedf699ed5534fade","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/usb/serial/quatech2.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.5","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.5","versionType":"semver"},{"version":"5.4.290","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.234","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.178","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.128","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.75","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.12","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.13.1","status":"unaffected","lessThanOrEqual":"6.13.*","versionType":"semver"},{"version":"6.14","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/usb/serial/quatech2.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/fa4c7472469d97c4707698b4c0e098f8cfc2bf22"},{"url":"https://git.kernel.org/stable/c/94770cf7c5124f0268d481886829dc2beecc4507"},{"url":"https://git.kernel.org/stable/c/6068dcff7f19e9fa6fa23ee03453ad6a40fa4efe"},{"url":"https://git.kernel.org/stable/c/4b9b41fabcd38990f69ef0cee9c631d954a2b530"},{"url":"https://git.kernel.org/stable/c/6377838560c03b36e1153a42ef727533def9b68f"},{"url":"https://git.kernel.org/stable/c/f371471708c7d997f763b0e70565026eb67cc470"},{"url":"https://git.kernel.org/stable/c/8542b33622571f54dfc2a267fce378b6e3840b8b"},{"url":"https://git.kernel.org/stable/c/575a5adf48b06a2980c9eeffedf699ed5534fade"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T21:04:31.416Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.5","versionEndExcluding":"5.4.290"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.5","versionEndExcluding":"5.10.234"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.5","versionEndExcluding":"5.15.178"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.5","versionEndExcluding":"6.1.128"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.5","versionEndExcluding":"6.6.75"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.5","versionEndExcluding":"6.12.12"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.5","versionEndExcluding":"6.13.1"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.5","versionEndExcluding":"6.14"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":5.5,"attackVector":"LOCAL","baseSeverity":"MEDIUM","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","integrityImpact":"NONE","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"HIGH","privilegesRequired":"LOW","confidentialityImpact":"NONE"}},{"other":{"type":"ssvc","content":{"id":"CVE-2025-21689","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2025-10-01T19:51:31.131902Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-476","lang":"en","type":"CWE","description":"CWE-476 NULL Pointer Dereference"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2025-10-01T19:57:10.344Z"}},{"title":"CVE Program Container","references":[{"url":"https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html"},{"url":"https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html"}],"providerMetadata":{"shortName":"CVE","orgId":"af854a3a-2127-422b-91ae-364da2661108","dateUpdated":"2025-11-03T20:59:10.756Z"}}]}}}