Skip to content
CVE PROGRAM SOURCE RECORD9.8 Critical

CVE-2026-89969

nvmet-tcp: fix out-of-bounds write when receiving an over-long PDU

Description

In the Linux kernel, the following vulnerability has been resolved: nvmet-tcp: fix out-of-bounds write when receiving an over-long PDU nvmet_tcp_try_recv_pdu() reads a PDU header into the fixed 128-byte queue->pdu union, then computes the remaining payload length as queue->left = hdr->hlen - queue->offset + hdgst; and reads that many more bytes into &queue->pdu + queue->offset, without ever bounding the result against sizeof(queue->pdu). A struct nvme_tcp_icreq_pdu is itself 128 bytes, exactly the size of the union. Once a header digest has been negotiated (hdgst = 4), a second ICReq passes the hlen == nvmet_tcp_pdu_size() check but yields queue->left = 128 - 8 + 4 = 124, so bytes 8..132 are written into the 128-byte buffer -- 4 bytes past its end, over queue->hdr_digest and queue->data_digest. Those bytes are attacker-controlled (an ICReq carries no digest), and the duplicate ICReq is only rejected later, after the overflow. A remote unauthenticated host can thus corrupt kernel memory adjacent to the receive buffer. Reject any PDU whose declared length would read past the end of queue->pdu before the second recv.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

Linux Linux

Default version status: unaffected

  • 872d26a391da92ed8f0c0f5cb5fef428067b7f30 to < a3f0bcfbaf3312a5754d1ce020a07d394669eb25affected
  • 872d26a391da92ed8f0c0f5cb5fef428067b7f30 to < 4f84d42c53c49557fb1ef285c683b0a81b576c74affected
  • 872d26a391da92ed8f0c0f5cb5fef428067b7f30 to < 58dc6035b79c4c73c0cbf9ec9f68a7f117b2b3e6affected
  • 872d26a391da92ed8f0c0f5cb5fef428067b7f30 to < cf5f39d2b58f97e0cd1829c4a6aeef17f1607ccaaffected
  • 872d26a391da92ed8f0c0f5cb5fef428067b7f30 to < 3a385e0c39efbe34db8edd95900c123113ae3450affected
  • 872d26a391da92ed8f0c0f5cb5fef428067b7f30 to < dbc4acbdb3ca8c81441368ad7409b8f77d4de8f6affected
  • 872d26a391da92ed8f0c0f5cb5fef428067b7f30 to < d95d342bc0ea82dc79e6362b2f1f997431750e4caffected
  • 872d26a391da92ed8f0c0f5cb5fef428067b7f30 to < 14cc5a7e77731497d5bea70f3bb05df7eda982e4affected

Linux Linux

Default version status: affected

  • 5.0affected
  • 0 to < 5.0unaffected
  • 5.10.270 to ≤ 5.10.*unaffected
  • 5.15.221 to ≤ 5.15.*unaffected
  • 6.1.188 to ≤ 6.1.*unaffected
  • 6.6.157 to ≤ 6.6.*unaffected
  • 6.12.110 to ≤ 6.12.*unaffected
  • 6.18.51 to ≤ 6.18.*unaffected
  • 7.2.5 to ≤ 7.2.*unaffected
  • 7.3 to ≤ *unaffected

References