{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-74429", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-15T05:44:03.895Z", "datePublished": "2026-08-15T05:59:30.286Z", "dateUpdated": "2026-08-17T05:47:04.412Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T05:47:04.412Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nrxrpc: Fix the reception of a reply packet before data transmission\n\nFix rxrpc_receiving_reply() to handle the reception of an apparent reply\nDATA packet before rxrpc has had a chance to send any request DATA packets\non a client call by checking to see if the call has been exposed yet by\nsending the first packet.\n\nWithout this, rxrpc_rotate_tx_window() might oops.\n\nAlso fix rxrpc_rotate_tx_window() to handle the Tx queue being empty by\nchanging the do...while loop into a while loop, just in case a call is\nabnormally terminated by an early reply before the last request packet is\ntransmitted." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:N - The bug is reached when a remote UDP RxRPC DATA reply is processed on an established client call via rxrpc_encap_rcv(), rxrpc_input_packet_on_conn(), and rxrpc_input_data(); a malicious or compromised AFS/RxRPC server peer can send that early reply over the network to any kAFS/AF_RXRPC client.\nAC:L - The remote server controls both sides of the timing race—it can send a reply DATA packet immediately after the client call is live on the channel but before RXRPC_CALL_EXPOSED/first transmit—and can retry on every RPC without depending on memory layout or other uncontrollable conditions.\nPR:N - No local credentials or kernel capabilities on the victim are required; exploitation only needs the attacker to act as the established RxRPC server peer able to send call-bound DATA packets on an active client connection after the normal security handshake.\nUI:N - Once the victim host has an active client call (normal kAFS file access or AF_RXRPC sendmsg), the kernel rxrpc I/O thread autonomously processes the attacker's early reply with no further interactive victim action at exploit time.\nS:U - The oops in rxrpc_rotate_tx_window() affects only kernel memory and threads within the same security authority on the client host; it does not cross VM, container, IOMMU, or sandbox boundaries.\nC:N - The defect is a NULL dereference from a do...while loop that executes once on an empty Tx queue when seq exceeds tx_top (tq or tq->bufs[ix] is NULL); this is a pure crash path, not an out-of-bounds read or use-after-free disclosure primitive.\nI:N - No attacker-controlled memory is written; the failure dereferences NULL or uninitialized txqueue entries before any buffer rotation or put_txbuf logic completes, yielding only a kernel fault without integrity modification capability.\nA:H - Without the fix, rxrpc_rotate_tx_window() oopses the rxrpc I/O kernel thread that services all RxRPC/AFS traffic on that endpoint; a malicious server can trigger this on every client RPC call, causing repeated kernel crashes or hangs." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/rxrpc/input.c" ], "versions": [ { "version": "b341a0263b1b804d329f864c2dc24815364510ec", "lessThan": "f9be514984471ff0003738b2e1efed12bc3433ff", "status": "affected", "versionType": "git" }, { "version": "b341a0263b1b804d329f864c2dc24815364510ec", "lessThan": "e220ae559e5a0fc33e41ec6a348ea50387cb8b0f", "status": "affected", "versionType": "git" }, { "version": "b341a0263b1b804d329f864c2dc24815364510ec", "lessThan": "a58e33405acd2584e730c1da72635f822ada6b49", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/rxrpc/input.c" ], "versions": [ { "version": "6.14", "status": "affected" }, { "version": "0", "lessThan": "6.14", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.40", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.5", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.14", "versionEndExcluding": "6.18.40" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.14", "versionEndExcluding": "7.1.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.14", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/f9be514984471ff0003738b2e1efed12bc3433ff" }, { "url": "https://git.kernel.org/stable/c/e220ae559e5a0fc33e41ec6a348ea50387cb8b0f" }, { "url": "https://git.kernel.org/stable/c/a58e33405acd2584e730c1da72635f822ada6b49" } ], "title": "rxrpc: Fix the reception of a reply packet before data transmission", "x_generator": { "engine": "bippy-1.2.0" } } } }