{"id":"CVE-2025-22003","state":"PUBLISHED","title":"can: ucan: fix out of bound read in strscpy() source","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ncan: ucan: fix out of bound read in strscpy() source\n\nCommit 7fdaf8966aae (\"can: ucan: use strscpy() to instead of strncpy()\")\nunintentionally introduced a one byte out of bound read on strscpy()'s\nsource argument (which is kind of ironic knowing that strscpy() is meant\nto be a more secure alternative :)).\n\nLet's consider below buffers:\n\n  dest[len + 1]; /* will be NUL terminated */\n  src[len]; /* may not be NUL terminated */\n\nWhen doing:\n\n  strncpy(dest, src, len);\n  dest[len] = '\\0';\n\nstrncpy() will read up to len bytes from src.\n\nOn the other hand:\n\n  strscpy(dest, src, len + 1);\n\nwill read up to len + 1 bytes from src, that is to say, an out of bound\nread of one byte will occur on src if it is not NUL terminated. Note\nthat the src[len] byte is never copied, but strscpy() still needs to\nread it to check whether a truncation occurred or not.\n\nThis exact pattern happened in ucan.\n\nThe root cause is that the source is not NUL terminated. Instead of\ndoing a copy in a local buffer, directly NUL terminate it as soon as\nusb_control_msg() returns. With this, the local firmware_str[] variable\ncan be removed.\n\nOn top of this do a couple refactors:\n\n  - ucan_ctl_payload->raw is only used for the firmware string, so\n    rename it to ucan_ctl_payload->fw_str and change its type from u8 to\n    char.\n\n  - ucan_device_request_in() is only used to retrieve the firmware\n    string, so rename it to ucan_get_fw_str() and refactor it to make it\n    directly handle all the string termination logic.","publishedAt":"2025-04-03T07:19:05.403Z","updatedAt":"2026-05-11T21:10:46.137Z","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":"7fdaf8966aae476deafe11f9a0067ff588615444","status":"affected","lessThan":"cc29775a8a72d7f3b56cc026796ad99bd65804a7","versionType":"git"},{"version":"7fdaf8966aae476deafe11f9a0067ff588615444","status":"affected","lessThan":"8cec9e314d3360fc1d8346297c41a6ee45cb45a9","versionType":"git"},{"version":"7fdaf8966aae476deafe11f9a0067ff588615444","status":"affected","lessThan":"a4994161a61bc8fd71d105c579d847cefee99262","versionType":"git"},{"version":"7fdaf8966aae476deafe11f9a0067ff588615444","status":"affected","lessThan":"1d22a122ffb116c3cf78053e812b8b21f8852ee9","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/can/usb/ucan.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.2","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.2","versionType":"semver"},{"version":"6.6.85","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.21","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.13.9","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/net/can/usb/ucan.c"]}],"references":["https://git.kernel.org/stable/c/cc29775a8a72d7f3b56cc026796ad99bd65804a7","https://git.kernel.org/stable/c/8cec9e314d3360fc1d8346297c41a6ee45cb45a9","https://git.kernel.org/stable/c/a4994161a61bc8fd71d105c579d847cefee99262","https://git.kernel.org/stable/c/1d22a122ffb116c3cf78053e812b8b21f8852ee9"],"weaknesses":["CWE-125"],"ingestedAt":"2026-10-29T20:08:39.238Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2025/22xxx/CVE-2025-22003.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-22003","state":"PUBLISHED","datePublished":"2025-04-03T07:19:05.403Z","dateUpdated":"2026-05-11T21:10:46.137Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2024-12-29T08:45:45.802Z"},"containers":{"cna":{"title":"can: ucan: fix out of bound read in strscpy() source","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ncan: ucan: fix out of bound read in strscpy() source\n\nCommit 7fdaf8966aae (\"can: ucan: use strscpy() to instead of strncpy()\")\nunintentionally introduced a one byte out of bound read on strscpy()'s\nsource argument (which is kind of ironic knowing that strscpy() is meant\nto be a more secure alternative :)).\n\nLet's consider below buffers:\n\n  dest[len + 1]; /* will be NUL terminated */\n  src[len]; /* may not be NUL terminated */\n\nWhen doing:\n\n  strncpy(dest, src, len);\n  dest[len] = '\\0';\n\nstrncpy() will read up to len bytes from src.\n\nOn the other hand:\n\n  strscpy(dest, src, len + 1);\n\nwill read up to len + 1 bytes from src, that is to say, an out of bound\nread of one byte will occur on src if it is not NUL terminated. Note\nthat the src[len] byte is never copied, but strscpy() still needs to\nread it to check whether a truncation occurred or not.\n\nThis exact pattern happened in ucan.\n\nThe root cause is that the source is not NUL terminated. Instead of\ndoing a copy in a local buffer, directly NUL terminate it as soon as\nusb_control_msg() returns. With this, the local firmware_str[] variable\ncan be removed.\n\nOn top of this do a couple refactors:\n\n  - ucan_ctl_payload->raw is only used for the firmware string, so\n    rename it to ucan_ctl_payload->fw_str and change its type from u8 to\n    char.\n\n  - ucan_device_request_in() is only used to retrieve the firmware\n    string, so rename it to ucan_get_fw_str() and refactor it to make it\n    directly handle all the string termination logic."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"7fdaf8966aae476deafe11f9a0067ff588615444","status":"affected","lessThan":"cc29775a8a72d7f3b56cc026796ad99bd65804a7","versionType":"git"},{"version":"7fdaf8966aae476deafe11f9a0067ff588615444","status":"affected","lessThan":"8cec9e314d3360fc1d8346297c41a6ee45cb45a9","versionType":"git"},{"version":"7fdaf8966aae476deafe11f9a0067ff588615444","status":"affected","lessThan":"a4994161a61bc8fd71d105c579d847cefee99262","versionType":"git"},{"version":"7fdaf8966aae476deafe11f9a0067ff588615444","status":"affected","lessThan":"1d22a122ffb116c3cf78053e812b8b21f8852ee9","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/can/usb/ucan.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.2","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.2","versionType":"semver"},{"version":"6.6.85","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.21","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.13.9","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/net/can/usb/ucan.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/cc29775a8a72d7f3b56cc026796ad99bd65804a7"},{"url":"https://git.kernel.org/stable/c/8cec9e314d3360fc1d8346297c41a6ee45cb45a9"},{"url":"https://git.kernel.org/stable/c/a4994161a61bc8fd71d105c579d847cefee99262"},{"url":"https://git.kernel.org/stable/c/1d22a122ffb116c3cf78053e812b8b21f8852ee9"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T21:10:46.137Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.2","versionEndExcluding":"6.6.85"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.2","versionEndExcluding":"6.12.21"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.2","versionEndExcluding":"6.13.9"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.2","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":{"timestamp":"2025-10-01T17:09:56.626610Z","id":"CVE-2025-22003","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-125","type":"CWE","lang":"en","description":"CWE-125 Out-of-bounds Read"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2025-10-01T17:09:59.255Z"}}]}}}