{ "affected": [ { "ranges": [ { "events": [ { "introduced": "b8d26b3be8b33682cf163274ed07479a70554633" }, { "fixed": "b1f3313e7b3e396e4985fea5c709477387e0a065" }, { "fixed": "228aaa620fe6a7bc8b5b21dd348b4836b1760c61" }, { "fixed": "0d9c0586af703890afe1bd0cfe641e3a3af1c32d" }, { "fixed": "44fe800ec13386c88bd5b32bcd1deaa1e17535d5" }, { "fixed": "71ec8bbfa4a183f1e623662f9cfbcd702e433bdb" }, { "fixed": "c345d9d0b3eefc990bb90cf565325785aab06aab" }, { "fixed": "48812c8103071d550d9ab4a3431be5bdc52255bc" }, { "fixed": "2488b5b4827e5415768afc8daf097e8eb83c98df" } ], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "type": "GIT" } ] }, { "package": { "ecosystem": "Linux", "name": "Kernel" }, "ranges": [ { "events": [ { "introduced": "3.10.0" }, { "fixed": "5.10.270" } ], "type": "ECOSYSTEM" }, { "events": [ { "introduced": "5.11.0" }, { "fixed": "5.15.221" } ], "type": "ECOSYSTEM" }, { "events": [ { "introduced": "5.16.0" }, { "fixed": "6.1.188" } ], "type": "ECOSYSTEM" }, { "events": [ { "introduced": "6.2.0" }, { "fixed": "6.6.157" } ], "type": "ECOSYSTEM" }, { "events": [ { "introduced": "6.7.0" }, { "fixed": "6.12.110" } ], "type": "ECOSYSTEM" }, { "events": [ { "introduced": "6.13.0" }, { "fixed": "6.18.52" } ], "type": "ECOSYSTEM" }, { "events": [ { "introduced": "6.19.0" }, { "fixed": "7.2.6" } ], "type": "ECOSYSTEM" } ] } ], "database_specific": { "cna_assigner": "Linux", "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90413.json" }, "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nIB/isert: reject login PDUs declaring more data than was received\n\nisert_login_recv_done() records how many bytes the HCA actually placed in\nthe login buffer, but nothing compares that against the length the login\nPDU's BHS declares. isert_rx_login_req() copies min(login_req_len,\nMAX_KEY_VALUE_PAIRS) bytes into login-\u003ereq_buf, and the login code then\nreads the declared length back out of that buffer - for the first PDU in\niscsi_target_locate_portal(),\n\n\tpayload_length = ntoh24(login_req-\u003edlength);\n\ttmpbuf = kmemdup_nul(login-\u003ereq_buf, payload_length, GFP_KERNEL);\n\nand for the ones after it in iscsi_decode_text_input(), reached from\niscsi_target_do_login().\n\nlogin-\u003ereq_buf is a fixed MAX_KEY_VALUE_PAIRS (8192) byte allocation, so\nan initiator that declares more than it sends reads off the end of it,\nbefore authentication and with the length under its control:\n\n BUG: KASAN: slab-out-of-bounds in kmemdup_nul+0x43/0x80\n Read of size 8193 at addr ffff8881056a8000 by task iscsi_np/167\n __asan_memcpy+0x23/0x60\n kmemdup_nul+0x43/0x80\n iscsi_target_locate_portal+0x48d/0x1180\n iscsi_target_login_thread+0x19a9/0x3350\n Allocated by task 167:\n __kmalloc_cache_noprof+0x158/0x370\n iscsi_target_login_thread+0x971/0x3350\n which belongs to the cache kmalloc-8k of size 8192\n allocated 8192-byte region\n\nFalsifying the second login PDU instead reaches the other reader, on the\nsame buffer:\n\n BUG: KASAN: slab-out-of-bounds in kmemdup_nul+0x43/0x80\n Read of size 8193 at addr ffff888104d10000 by task kworker/1:1/50\n Workqueue: isert_login_wq iscsi_target_do_login_rx\n __asan_memcpy+0x23/0x60\n kmemdup_nul+0x43/0x80\n iscsi_decode_text_input+0xc6/0x11c0\n iscsi_target_do_login+0x261/0x1470\n iscsi_target_do_login_rx+0x51d/0x7d0\n\niscsit over TCP is not exposed: iscsit_get_login_rx() validates the\ndeclared length with iscsi_target_check_login_request() and then reads\nexactly that many bytes off the socket, so the declared length governs\nhow much arrives rather than how much is copied out of an already-filled\nbuffer. isert does not call iscsi_target_check_login_request() at all.\n\nReject a login PDU whose declared DataSegmentLength exceeds what was\nreceived, in both paths that reach isert_rx_login_req():\nisert_get_login_rx() for the first login PDU and isert_login_recv_done()\nfor the ones after it. dlength \u003c= login_req_len is allowed because the\nreceived count can include up to three bytes of iSCSI padding.\n\nOnce the check is in place the copy out can no longer exceed the copy in:\nthe posted login SGE is ISER_RX_PAYLOAD_SIZE, so login_req_len cannot\nexceed MAX_KEY_VALUE_PAIRS and the min() in isert_rx_login_req() is\nlogin_req_len.\n\nLike the existing short-PDU check added by 29e7b925ae6d, the reject in\nisert_login_recv_done() returns without completing login_req_comp, so a\nmalformed subsequent PDU leaves the login to be torn down by the login\ntimer rather than failing immediately. The first-PDU path returns an\nerror and fails straight away.\n\nReproduced on 7.2.0-rc4 with soft-RoCE (rdma_rxe) under KASAN, using an\ninitiator that sends the real key=value payload while declaring 8193 in\nthe BHS, on the first login PDU and on the second in separate runs. The\nreported read size tracks the declared value exactly; 16384 and 61440\nbehave the same. Unpatched 3 of 3 runs report on each of the two paths,\npatched 0 of 3 on both, run alternately in a single session, and a normal\nlogin still completes on the patched build.", "id": "CVE-2026-90413", "modified": "2026-09-19T03:30:51.084403720Z", "published": "2026-09-17T16:09:39.383Z", "references": [ { "type": "WEB", "url": "https://git.kernel.org/stable/c/0d9c0586af703890afe1bd0cfe641e3a3af1c32d" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/228aaa620fe6a7bc8b5b21dd348b4836b1760c61" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/2488b5b4827e5415768afc8daf097e8eb83c98df" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/44fe800ec13386c88bd5b32bcd1deaa1e17535d5" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/48812c8103071d550d9ab4a3431be5bdc52255bc" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/71ec8bbfa4a183f1e623662f9cfbcd702e433bdb" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/b1f3313e7b3e396e4985fea5c709477387e0a065" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/c345d9d0b3eefc990bb90cf565325785aab06aab" }, { "type": "ADVISORY", "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90413.json" }, { "type": "ADVISORY", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-90413" }, { "type": "PACKAGE", "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git" } ], "schema_version": "1.9.0", "severity": [ { "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H", "type": "CVSS_V3" } ], "summary": "IB/isert: reject login PDUs declaring more data than was received" }