{"id":"CVE-2023-53676","state":"PUBLISHED","title":"scsi: target: iscsi: Fix buffer overflow in lio_target_nacl_info_show()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: target: iscsi: Fix buffer overflow in lio_target_nacl_info_show()\n\nThe function lio_target_nacl_info_show() uses sprintf() in a loop to print\ndetails for every iSCSI connection in a session without checking for the\nbuffer length. With enough iSCSI connections it's possible to overflow the\nbuffer provided by configfs and corrupt the memory.\n\nThis patch replaces sprintf() with sysfs_emit_at() that checks for buffer\nboundries.","publishedAt":"2025-10-07T15:21:31.757Z","updatedAt":"2026-10-15T21:41:33.205Z","severity":{"score":8.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"e48354ce078c079996f89d715dfa44814b4eba01","status":"affected","lessThan":"df349e84c2cb0dd05d98c8e1189c26ab4b116083","versionType":"git"},{"version":"e48354ce078c079996f89d715dfa44814b4eba01","status":"affected","lessThan":"114b44dddea1f8f99576de3c0e6e9059012002fc","versionType":"git"},{"version":"e48354ce078c079996f89d715dfa44814b4eba01","status":"affected","lessThan":"2cbe6a88fbdd6e8aeab358eef61472e2de43d6f6","versionType":"git"},{"version":"e48354ce078c079996f89d715dfa44814b4eba01","status":"affected","lessThan":"bbe3ff47bf09db8956bc2eeb49d2d514d256ad2a","versionType":"git"},{"version":"e48354ce078c079996f89d715dfa44814b4eba01","status":"affected","lessThan":"5353df78c22623b42a71d51226d228a8413097e2","versionType":"git"},{"version":"e48354ce078c079996f89d715dfa44814b4eba01","status":"affected","lessThan":"4738bf8b2d3635c2944b81b2a84d97b8c8b0978d","versionType":"git"},{"version":"e48354ce078c079996f89d715dfa44814b4eba01","status":"affected","lessThan":"0cac6cbb9908309352a5d30c1876882771d3da50","versionType":"git"},{"version":"e48354ce078c079996f89d715dfa44814b4eba01","status":"affected","lessThan":"801f287c93ff95582b0a2d2163f12870a2f076d4","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/target/iscsi/iscsi_target_configfs.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.1","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.1","versionType":"semver"},{"version":"4.14.326","status":"unaffected","lessThanOrEqual":"4.14.*","versionType":"semver"},{"version":"4.19.295","status":"unaffected","lessThanOrEqual":"4.19.*","versionType":"semver"},{"version":"5.4.257","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.197","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.133","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.55","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.5.5","status":"unaffected","lessThanOrEqual":"6.5.*","versionType":"semver"},{"version":"6.6","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/target/iscsi/iscsi_target_configfs.c"]}],"references":["https://git.kernel.org/stable/c/df349e84c2cb0dd05d98c8e1189c26ab4b116083","https://git.kernel.org/stable/c/114b44dddea1f8f99576de3c0e6e9059012002fc","https://git.kernel.org/stable/c/2cbe6a88fbdd6e8aeab358eef61472e2de43d6f6","https://git.kernel.org/stable/c/bbe3ff47bf09db8956bc2eeb49d2d514d256ad2a","https://git.kernel.org/stable/c/5353df78c22623b42a71d51226d228a8413097e2","https://git.kernel.org/stable/c/4738bf8b2d3635c2944b81b2a84d97b8c8b0978d","https://git.kernel.org/stable/c/0cac6cbb9908309352a5d30c1876882771d3da50","https://git.kernel.org/stable/c/801f287c93ff95582b0a2d2163f12870a2f076d4"],"weaknesses":[],"ingestedAt":"2026-10-29T20:06:33.064Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2023/53xxx/CVE-2023-53676.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2023-53676","state":"PUBLISHED","datePublished":"2025-10-07T15:21:31.757Z","dateUpdated":"2026-10-15T21:41:33.205Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-10-07T15:16:59.664Z"},"containers":{"cna":{"title":"scsi: target: iscsi: Fix buffer overflow in lio_target_nacl_info_show()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: target: iscsi: Fix buffer overflow in lio_target_nacl_info_show()\n\nThe function lio_target_nacl_info_show() uses sprintf() in a loop to print\ndetails for every iSCSI connection in a session without checking for the\nbuffer length. With enough iSCSI connections it's possible to overflow the\nbuffer provided by configfs and corrupt the memory.\n\nThis patch replaces sprintf() with sysfs_emit_at() that checks for buffer\nboundries."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"e48354ce078c079996f89d715dfa44814b4eba01","status":"affected","lessThan":"df349e84c2cb0dd05d98c8e1189c26ab4b116083","versionType":"git"},{"version":"e48354ce078c079996f89d715dfa44814b4eba01","status":"affected","lessThan":"114b44dddea1f8f99576de3c0e6e9059012002fc","versionType":"git"},{"version":"e48354ce078c079996f89d715dfa44814b4eba01","status":"affected","lessThan":"2cbe6a88fbdd6e8aeab358eef61472e2de43d6f6","versionType":"git"},{"version":"e48354ce078c079996f89d715dfa44814b4eba01","status":"affected","lessThan":"bbe3ff47bf09db8956bc2eeb49d2d514d256ad2a","versionType":"git"},{"version":"e48354ce078c079996f89d715dfa44814b4eba01","status":"affected","lessThan":"5353df78c22623b42a71d51226d228a8413097e2","versionType":"git"},{"version":"e48354ce078c079996f89d715dfa44814b4eba01","status":"affected","lessThan":"4738bf8b2d3635c2944b81b2a84d97b8c8b0978d","versionType":"git"},{"version":"e48354ce078c079996f89d715dfa44814b4eba01","status":"affected","lessThan":"0cac6cbb9908309352a5d30c1876882771d3da50","versionType":"git"},{"version":"e48354ce078c079996f89d715dfa44814b4eba01","status":"affected","lessThan":"801f287c93ff95582b0a2d2163f12870a2f076d4","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/target/iscsi/iscsi_target_configfs.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.1","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.1","versionType":"semver"},{"version":"4.14.326","status":"unaffected","lessThanOrEqual":"4.14.*","versionType":"semver"},{"version":"4.19.295","status":"unaffected","lessThanOrEqual":"4.19.*","versionType":"semver"},{"version":"5.4.257","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.197","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.133","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.55","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.5.5","status":"unaffected","lessThanOrEqual":"6.5.*","versionType":"semver"},{"version":"6.6","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/target/iscsi/iscsi_target_configfs.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/df349e84c2cb0dd05d98c8e1189c26ab4b116083"},{"url":"https://git.kernel.org/stable/c/114b44dddea1f8f99576de3c0e6e9059012002fc"},{"url":"https://git.kernel.org/stable/c/2cbe6a88fbdd6e8aeab358eef61472e2de43d6f6"},{"url":"https://git.kernel.org/stable/c/bbe3ff47bf09db8956bc2eeb49d2d514d256ad2a"},{"url":"https://git.kernel.org/stable/c/5353df78c22623b42a71d51226d228a8413097e2"},{"url":"https://git.kernel.org/stable/c/4738bf8b2d3635c2944b81b2a84d97b8c8b0978d"},{"url":"https://git.kernel.org/stable/c/0cac6cbb9908309352a5d30c1876882771d3da50"},{"url":"https://git.kernel.org/stable/c/801f287c93ff95582b0a2d2163f12870a2f076d4"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","baseScore":8.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:N - The attacker-controlled state that causes the overflow — the number of MC/S connections on a session, plus the InitiatorName/InitiatorAlias/CID/peer-address bytes written OOB — is delivered entirely over TCP/3260 to the network-bound LIO iSCSI target from an arbitrary number of network hops away. This is the stored-payload pattern: the payload is planted remotely at the iSCSI protocol level and rendered later.\nAC:L - On an MC/S-enabled target (the deployment this was reported against) the attacker deterministically opens the ~25+ connections needed to exceed the 4096-byte page; no race, no memory-layout guess, no unpredictable condition is involved. Each additional login reliably extends the overflow.\nPR:N - iSCSI targets are very commonly run with CHAP disabled (`authentication=0`, or demo mode), and the initiator IQN matching an ACL is merely a string the peer asserts in the login PDU, so an unauthenticated remote peer can establish the multi-connection session. Even the connection-count growth occurs during login processing before any real credential check in that configuration.\nUI:R - The overflow executes when the world-readable configfs attribute `acls/<iqn>/info` is read — by an administrator, targetcli/rtslib, or a monitoring agent — which the remote attacker cannot initiate. That read is routine on managed storage nodes but is still a separate party's action.\nS:U - The corruption is kernel memory overwritten by kernel code within the same security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - Unbounded page-overflow with attacker-influenced content into adjacent buddy-allocator pages is a memory-corruption primitive that can be steered into slab objects, pointers, or page metadata and leveraged for arbitrary kernel memory disclosure.\nI:H - This is an out-of-bounds write of attacker-controlled length (scaling with connection count, up to megabytes) with partly attacker-chosen bytes (CIDs, peer addresses, StatSN) past the end of a kernel page, giving a strong write primitive suitable for control-flow hijack.\nA:H - Overwriting arbitrary adjacent kernel pages while holding `conn_lock` and `nacl_sess_lock` reliably corrupts unrelated kernel state and causes oops/panic; the attacker can repeat it on every read."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T09:15:29.713Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.1","versionEndExcluding":"4.14.326"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.1","versionEndExcluding":"4.19.295"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.1","versionEndExcluding":"5.4.257"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.1","versionEndExcluding":"5.10.197"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.1","versionEndExcluding":"5.15.133"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.1","versionEndExcluding":"6.1.55"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.1","versionEndExcluding":"6.5.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.1","versionEndExcluding":"6.6"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2023-53676","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-15T21:36:24.101967Z"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-15T21:41:33.205Z"}}]}}}