CVE-2026-89532 (GCVE-0-2026-89532)

Vulnerability from cvelistv5 – Published: 2026-09-11 19:44 – Updated: 2026-10-19 08:48
VLAI
Title
svcrdma: Fix pcl_for_each_segment for empty chunks
Summary
In the Linux kernel, the following vulnerability has been resolved: svcrdma: Fix pcl_for_each_segment for empty chunks When a parsed chunk list contains a chunk whose ch_segcount is zero, pcl_for_each_segment computes its inclusive upper bound as &chunk->ch_segments[ch_segcount - 1]. ch_segcount is u32, so the subtraction wraps to 0xFFFFFFFF and the bound lands far past the ch_segments flex array. The loop body then walks unrelated memory at sizeof(struct svc_rdma_segment) stride until it faults. A zero-segcount chunk is reachable from the wire: xdr_check_write_chunk() only rejects segcount values greater than rc_maxpages, and pcl_alloc_write() links a freshly allocated chunk onto rc_write_pcl/rc_reply_pcl before its segment-fill loop runs, so a Write or Reply chunk advertising zero segments leaves ch_segcount == 0 on the list. When the transport has negotiated Send-With-Invalidate, svc_rdma_get_inv_rkey() iterates all four PCLs with pcl_for_each_segment and dereferences segment->rs_handle on each iteration, turning the underflow into an out-of-bounds read and a general protection fault. xdr_check_write_list / xdr_check_reply_chunk pcl_alloc_write() chunk = pcl_alloc_chunk(...) /* ch_segcount = 0 */ list_add_tail(&chunk->ch_list, &pcl->cl_chunks) /* fill loop iterates zero times for wire segcount 0 */ svc_rdma_get_inv_rkey() pcl_for_each_chunk(rc_write_pcl) pcl_for_each_segment(segment, chunk) pos <= &ch_segments[0u - 1u] /* 0xFFFFFFFF */ segment->rs_handle /* OOB read -> GPF */ Fix by switching the macro to a half-open upper bound that uses ch_segcount directly. For ch_segcount == 0 the loop start equals the loop end and the body is skipped; for ch_segcount > 0 the iteration range is unchanged. All six existing call sites in net/sunrpc/xprtrdma/svc_rdma_recvfrom.c and net/sunrpc/xprtrdma/svc_rdma_rw.c remain correct under the new bound, so no caller changes are needed.
Severity
9.1 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-16 19:23 UTC
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 7018 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 78147ca8b4a9b6cf0e597ddd6bf17959e08376c2 , < 1e2e3481e39103a386b86be1c33eaef97cbdf16e (git)
Affected: 78147ca8b4a9b6cf0e597ddd6bf17959e08376c2 , < 3a78b841879c2a3243f74edc514236fb2907167f (git)
Affected: 78147ca8b4a9b6cf0e597ddd6bf17959e08376c2 , < 06d0390c37fa6714624af771bd72bbf1a7ed9bb1 (git)
Affected: 78147ca8b4a9b6cf0e597ddd6bf17959e08376c2 , < 9c5a03c3dc505c0295339b0a1b9e4fe36447e482 (git)
Affected: 78147ca8b4a9b6cf0e597ddd6bf17959e08376c2 , < a1c954ca4977a4e6ec73ef92fe48073ec54f9fc8 (git)
Affected: 78147ca8b4a9b6cf0e597ddd6bf17959e08376c2 , < 6d33a7e6bf6c6b293a266a617201285a1ad32c56 (git)
Affected: 78147ca8b4a9b6cf0e597ddd6bf17959e08376c2 , < b7713a784c59515d0aba558c8f5df6a0164dd3a9 (git)
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Linux Linux Affected: 5.11
Unaffected: 0 , < 5.11 (semver)
Unaffected: 5.15.221 , ≤ 5.15.* (semver)
Unaffected: 6.1.188 , ≤ 6.1.* (semver)
Unaffected: 6.6.157 , ≤ 6.6.* (semver)
Unaffected: 6.12.109 , ≤ 6.12.* (semver)
Unaffected: 6.18.50 , ≤ 6.18.* (semver)
Unaffected: 7.2.4 , ≤ 7.2.* (semver)
Unaffected: 7.3 , ≤ * (original_commit_for_fix)
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsvcrdma: Fix pcl_for_each_segment for empty chunks\n\nWhen a parsed chunk list contains a chunk whose ch_segcount is zero,\npcl_for_each_segment computes its inclusive upper bound as\n\u0026chunk-\u003ech_segments[ch_segcount - 1]. ch_segcount is u32, so the\nsubtraction wraps to 0xFFFFFFFF and the bound lands far past the\nch_segments flex array. The loop body then walks unrelated memory at\nsizeof(struct svc_rdma_segment) stride until it faults.\n\nA zero-segcount chunk is reachable from the wire:\nxdr_check_write_chunk() only rejects segcount values greater than\nrc_maxpages, and pcl_alloc_write() links a freshly allocated chunk\nonto rc_write_pcl/rc_reply_pcl before its segment-fill loop runs,\nso a Write or Reply chunk advertising zero segments leaves\nch_segcount == 0 on the list. When the transport has negotiated\nSend-With-Invalidate, svc_rdma_get_inv_rkey() iterates all four\nPCLs with pcl_for_each_segment and dereferences segment-\u003ers_handle\non each iteration, turning the underflow into an out-of-bounds read\nand a general protection fault.\n\n    xdr_check_write_list / xdr_check_reply_chunk\n      pcl_alloc_write()\n        chunk = pcl_alloc_chunk(...)  /* ch_segcount = 0 */\n        list_add_tail(\u0026chunk-\u003ech_list, \u0026pcl-\u003ecl_chunks)\n        /* fill loop iterates zero times for wire segcount 0 */\n\n    svc_rdma_get_inv_rkey()\n      pcl_for_each_chunk(rc_write_pcl)\n        pcl_for_each_segment(segment, chunk)\n          pos \u003c= \u0026ch_segments[0u - 1u]  /* 0xFFFFFFFF */\n          segment-\u003ers_handle            /* OOB read -\u003e GPF */\n\nFix by switching the macro to a half-open upper bound that uses\nch_segcount directly. For ch_segcount == 0 the loop start equals the\nloop end and the body is skipped; for ch_segcount \u003e 0 the iteration\nrange is unchanged. All six existing call sites in\nnet/sunrpc/xprtrdma/svc_rdma_recvfrom.c and\nnet/sunrpc/xprtrdma/svc_rdma_rw.c remain correct under the new bound,\nso no caller changes are needed."
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              "value": "AV:N - svcrdma is the nfsd RPC-over-RDMA server transport and parses Write/Reply chunks from remote peers over iWARP or routable RoCEv2; a remote NFS/RDMA client triggers the bug with a crafted transport header on an established RDMA connection.\nAC:L - The attacker sets RPCRDMA_CMP_F_SND_W_INV_OK on connect and sends a Write or Reply chunk with segcount 0, which xdr_check_write_chunk accepts; Send-With-Invalidate is available on typical RDMA devices, so svc_rdma_get_inv_rkey hits the underflow deterministically.\nPR:N - svc_rdma_xdr_decode_req and svc_rdma_get_inv_rkey run in svc_rdma_recvfrom before svc_process/svc_authenticate; RDMA CM accept and RPC-over-RDMA header parsing require no NFS credentials or capabilities.\nUI:N - Exploitation requires only attacker-generated RDMA connect and RPC-over-RDMA messages to a listening NFS/RDMA service; no victim user action is needed.\nS:U - The out-of-bounds read and resulting general protection fault occur in the host kernel NFS/RDMA server and do not cross a VM, IOMMU, or sandbox boundary.\nC:H - With ch_segcount 0, pcl_for_each_segment underflows the u32 bound to 0xFFFFFFFF and walks adjacent kernel heap at sizeof(struct svc_rdma_segment) stride, an unbounded out-of-bounds read rather than a few-byte leak.\nI:N - svc_rdma_get_inv_rkey only loads segment-\u003ers_handle from the overrun pointer; the defect is a read-only walk with no out-of-bounds write, use-after-free, or control-flow hijack primitive.\nA:H - The unbounded walk continues until it hits unmapped memory and raises a general protection fault, oopsing or panicking the kernel, and the attacker can repeat it on each request."
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            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsvcrdma: Fix pcl_for_each_segment for empty chunks\n\nWhen a parsed chunk list contains a chunk whose ch_segcount is zero,\npcl_for_each_segment computes its inclusive upper bound as\n\u0026chunk-\u003ech_segments[ch_segcount - 1]. ch_segcount is u32, so the\nsubtraction wraps to 0xFFFFFFFF and the bound lands far past the\nch_segments flex array. The loop body then walks unrelated memory at\nsizeof(struct svc_rdma_segment) stride until it faults.\n\nA zero-segcount chunk is reachable from the wire:\nxdr_check_write_chunk() only rejects segcount values greater than\nrc_maxpages, and pcl_alloc_write() links a freshly allocated chunk\nonto rc_write_pcl/rc_reply_pcl before its segment-fill loop runs,\nso a Write or Reply chunk advertising zero segments leaves\nch_segcount == 0 on the list. When the transport has negotiated\nSend-With-Invalidate, svc_rdma_get_inv_rkey() iterates all four\nPCLs with pcl_for_each_segment and dereferences segment-\u003ers_handle\non each iteration, turning the underflow into an out-of-bounds read\nand a general protection fault.\n\n    xdr_check_write_list / xdr_check_reply_chunk\n      pcl_alloc_write()\n        chunk = pcl_alloc_chunk(...)  /* ch_segcount = 0 */\n        list_add_tail(\u0026chunk-\u003ech_list, \u0026pcl-\u003ecl_chunks)\n        /* fill loop iterates zero times for wire segcount 0 */\n\n    svc_rdma_get_inv_rkey()\n      pcl_for_each_chunk(rc_write_pcl)\n        pcl_for_each_segment(segment, chunk)\n          pos \u003c= \u0026ch_segments[0u - 1u]  /* 0xFFFFFFFF */\n          segment-\u003ers_handle            /* OOB read -\u003e GPF */\n\nFix by switching the macro to a half-open upper bound that uses\nch_segcount directly. For ch_segcount == 0 the loop start equals the\nloop end and the body is skipped; for ch_segcount \u003e 0 the iteration\nrange is unchanged. All six existing call sites in\nnet/sunrpc/xprtrdma/svc_rdma_recvfrom.c and\nnet/sunrpc/xprtrdma/svc_rdma_rw.c remain correct under the new bound,\nso no caller changes are needed."
          }
        ],
        "id": "CVE-2026-89532",
        "lastModified": "2026-10-19T09:17:47.770",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 9.1,
                "baseSeverity": "CRITICAL",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "NONE",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 3.9,
              "impactScore": 5.2,
              "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
              "type": "Secondary"
            }
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          "ssvcV203": [
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              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "ssvcData": {
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                "options": [
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                  },
                  {
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                  },
                  {
                    "technicalImpact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-10-16T19:23:11.362883Z",
                "version": "2.0.3"
              }
            }
          ]
        },
        "published": "2026-09-11T20:19:36.117",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/06d0390c37fa6714624af771bd72bbf1a7ed9bb1"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/1e2e3481e39103a386b86be1c33eaef97cbdf16e"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/3a78b841879c2a3243f74edc514236fb2907167f"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/6d33a7e6bf6c6b293a266a617201285a1ad32c56"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/9c5a03c3dc505c0295339b0a1b9e4fe36447e482"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/a1c954ca4977a4e6ec73ef92fe48073ec54f9fc8"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/b7713a784c59515d0aba558c8f5df6a0164dd3a9"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Received"
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-10-30T07:04:49+00:00",
      "cve": "CVE-2026-89532",
      "id": "CVE-2026-89532",
      "initial_release_date": "2026-09-11T00:00:00+00:00",
      "product_status:known_affected": "237",
      "product_status:known_not_affected": "42",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: svcrdma: Fix pcl_for_each_segment for empty chunks",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89532.json",
      "version": "3"
    },
    "vulnrichment": {
      "containers": {
        "adp": [
          {
            "metrics": [
              {
                "other": {
                  "content": {
                    "id": "CVE-2026-89532",
                    "options": [
                      {
                        "Exploitation": "none"
                      },
                      {
                        "Automatable": "yes"
                      },
                      {
                        "Technical Impact": "partial"
                      }
                    ],
                    "role": "CISA Coordinator",
                    "timestamp": "2026-10-16T19:23:11.362883Z",
                    "version": "2.0.3"
                  },
                  "type": "ssvc"
                }
              }
            ],
            "providerMetadata": {
              "dateUpdated": "2026-10-16T19:23:11.910Z",
              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP"
            },
            "title": "CISA ADP Vulnrichment"
          }
        ],
        "cna": {
          "affected": [
            {
              "defaultStatus": "unaffected",
              "product": "Linux",
              "programFiles": [
                "include/linux/sunrpc/svc_rdma_pcl.h"
              ],
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "vendor": "Linux",
              "versions": [
                {
                  "lessThan": "1e2e3481e39103a386b86be1c33eaef97cbdf16e",
                  "status": "affected",
                  "version": "78147ca8b4a9b6cf0e597ddd6bf17959e08376c2",
                  "versionType": "git"
                },
                {
                  "lessThan": "3a78b841879c2a3243f74edc514236fb2907167f",
                  "status": "affected",
                  "version": "78147ca8b4a9b6cf0e597ddd6bf17959e08376c2",
                  "versionType": "git"
                },
                {
                  "lessThan": "06d0390c37fa6714624af771bd72bbf1a7ed9bb1",
                  "status": "affected",
                  "version": "78147ca8b4a9b6cf0e597ddd6bf17959e08376c2",
                  "versionType": "git"
                },
                {
                  "lessThan": "9c5a03c3dc505c0295339b0a1b9e4fe36447e482",
                  "status": "affected",
                  "version": "78147ca8b4a9b6cf0e597ddd6bf17959e08376c2",
                  "versionType": "git"
                },
                {
                  "lessThan": "a1c954ca4977a4e6ec73ef92fe48073ec54f9fc8",
                  "status": "affected",
                  "version": "78147ca8b4a9b6cf0e597ddd6bf17959e08376c2",
                  "versionType": "git"
                },
                {
                  "lessThan": "6d33a7e6bf6c6b293a266a617201285a1ad32c56",
                  "status": "affected",
                  "version": "78147ca8b4a9b6cf0e597ddd6bf17959e08376c2",
                  "versionType": "git"
                },
                {
                  "lessThan": "b7713a784c59515d0aba558c8f5df6a0164dd3a9",
                  "status": "affected",
                  "version": "78147ca8b4a9b6cf0e597ddd6bf17959e08376c2",
                  "versionType": "git"
                }
              ]
            },
            {
              "defaultStatus": "affected",
              "product": "Linux",
              "programFiles": [
                "include/linux/sunrpc/svc_rdma_pcl.h"
              ],
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "vendor": "Linux",
              "versions": [
                {
                  "status": "affected",
                  "version": "5.11"
                },
                {
                  "lessThan": "5.11",
                  "status": "unaffected",
                  "version": "0",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "5.15.*",
                  "status": "unaffected",
                  "version": "5.15.221",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "6.1.*",
                  "status": "unaffected",
                  "version": "6.1.188",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "6.6.*",
                  "status": "unaffected",
                  "version": "6.6.157",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "6.12.*",
                  "status": "unaffected",
                  "version": "6.12.109",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "6.18.*",
                  "status": "unaffected",
                  "version": "6.18.50",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "7.2.*",
                  "status": "unaffected",
                  "version": "7.2.4",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "*",
                  "status": "unaffected",
                  "version": "7.3",
                  "versionType": "original_commit_for_fix"
                }
              ]
            }
          ],
          "cpeApplicability": [
            {
              "nodes": [
                {
                  "cpeMatch": [
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "5.15.221",
                      "versionStartIncluding": "5.11",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "6.1.188",
                      "versionStartIncluding": "5.11",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "6.6.157",
                      "versionStartIncluding": "5.11",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "6.12.109",
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                      "vulnerable": true
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                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "6.18.50",
                      "versionStartIncluding": "5.11",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "7.2.4",
                      "versionStartIncluding": "5.11",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "7.3",
                      "versionStartIncluding": "5.11",
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                  ],
                  "negate": false,
                  "operator": "OR"
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          ],
          "descriptions": [
            {
              "lang": "en",
              "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsvcrdma: Fix pcl_for_each_segment for empty chunks\n\nWhen a parsed chunk list contains a chunk whose ch_segcount is zero,\npcl_for_each_segment computes its inclusive upper bound as\n\u0026chunk-\u003ech_segments[ch_segcount - 1]. ch_segcount is u32, so the\nsubtraction wraps to 0xFFFFFFFF and the bound lands far past the\nch_segments flex array. The loop body then walks unrelated memory at\nsizeof(struct svc_rdma_segment) stride until it faults.\n\nA zero-segcount chunk is reachable from the wire:\nxdr_check_write_chunk() only rejects segcount values greater than\nrc_maxpages, and pcl_alloc_write() links a freshly allocated chunk\nonto rc_write_pcl/rc_reply_pcl before its segment-fill loop runs,\nso a Write or Reply chunk advertising zero segments leaves\nch_segcount == 0 on the list. When the transport has negotiated\nSend-With-Invalidate, svc_rdma_get_inv_rkey() iterates all four\nPCLs with pcl_for_each_segment and dereferences segment-\u003ers_handle\non each iteration, turning the underflow into an out-of-bounds read\nand a general protection fault.\n\n    xdr_check_write_list / xdr_check_reply_chunk\n      pcl_alloc_write()\n        chunk = pcl_alloc_chunk(...)  /* ch_segcount = 0 */\n        list_add_tail(\u0026chunk-\u003ech_list, \u0026pcl-\u003ecl_chunks)\n        /* fill loop iterates zero times for wire segcount 0 */\n\n    svc_rdma_get_inv_rkey()\n      pcl_for_each_chunk(rc_write_pcl)\n        pcl_for_each_segment(segment, chunk)\n          pos \u003c= \u0026ch_segments[0u - 1u]  /* 0xFFFFFFFF */\n          segment-\u003ers_handle            /* OOB read -\u003e GPF */\n\nFix by switching the macro to a half-open upper bound that uses\nch_segcount directly. For ch_segcount == 0 the loop start equals the\nloop end and the body is skipped; for ch_segcount \u003e 0 the iteration\nrange is unchanged. All six existing call sites in\nnet/sunrpc/xprtrdma/svc_rdma_recvfrom.c and\nnet/sunrpc/xprtrdma/svc_rdma_rw.c remain correct under the new bound,\nso no caller changes are needed."
            }
          ],
          "metrics": [
            {
              "cvssV3_1": {
                "baseScore": 9.1,
                "baseSeverity": "CRITICAL",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H",
                "version": "3.1"
              },
              "scenarios": [
                {
                  "lang": "en",
                  "value": "AV:N - svcrdma is the nfsd RPC-over-RDMA server transport and parses Write/Reply chunks from remote peers over iWARP or routable RoCEv2; a remote NFS/RDMA client triggers the bug with a crafted transport header on an established RDMA connection.\nAC:L - The attacker sets RPCRDMA_CMP_F_SND_W_INV_OK on connect and sends a Write or Reply chunk with segcount 0, which xdr_check_write_chunk accepts; Send-With-Invalidate is available on typical RDMA devices, so svc_rdma_get_inv_rkey hits the underflow deterministically.\nPR:N - svc_rdma_xdr_decode_req and svc_rdma_get_inv_rkey run in svc_rdma_recvfrom before svc_process/svc_authenticate; RDMA CM accept and RPC-over-RDMA header parsing require no NFS credentials or capabilities.\nUI:N - Exploitation requires only attacker-generated RDMA connect and RPC-over-RDMA messages to a listening NFS/RDMA service; no victim user action is needed.\nS:U - The out-of-bounds read and resulting general protection fault occur in the host kernel NFS/RDMA server and do not cross a VM, IOMMU, or sandbox boundary.\nC:H - With ch_segcount 0, pcl_for_each_segment underflows the u32 bound to 0xFFFFFFFF and walks adjacent kernel heap at sizeof(struct svc_rdma_segment) stride, an unbounded out-of-bounds read rather than a few-byte leak.\nI:N - svc_rdma_get_inv_rkey only loads segment-\u003ers_handle from the overrun pointer; the defect is a read-only walk with no out-of-bounds write, use-after-free, or control-flow hijack primitive.\nA:H - The unbounded walk continues until it hits unmapped memory and raises a general protection fault, oopsing or panicking the kernel, and the attacker can repeat it on each request."
                }
              ]
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2026-10-19T08:48:23.895Z",
            "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "shortName": "Linux"
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          "references": [
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              "url": "https://git.kernel.org/stable/c/1e2e3481e39103a386b86be1c33eaef97cbdf16e"
            },
            {
              "url": "https://git.kernel.org/stable/c/3a78b841879c2a3243f74edc514236fb2907167f"
            },
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            },
            {
              "url": "https://git.kernel.org/stable/c/b7713a784c59515d0aba558c8f5df6a0164dd3a9"
            }
          ],
          "title": "svcrdma: Fix pcl_for_each_segment for empty chunks",
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        "assignerShortName": "Linux",
        "cveId": "CVE-2026-89532",
        "datePublished": "2026-09-11T19:44:11.495Z",
        "dateReserved": "2026-09-11T19:38:34.720Z",
        "dateUpdated": "2026-10-19T08:48:23.895Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
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  }
}



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