Vulnerability-Lookup

GHSA-P5W3-Q665-Q5V8

Vulnerability from github – Published: 2026-09-11 21:31 – Updated: 2026-09-13 09:32

Details

In the Linux kernel, the following vulnerability has been resolved:

crypto: iaa - unmap dst before software fallback on decompress

On a hardware analytics error, decompress retries through the software fallback, which writes req->dst with the CPU while it is still mapped DMA_FROM_DEVICE. With SWIOTLB active the later dma_unmap_sg() copies the stale bounce buffer over req->dst, corrupting the result.

Unmap before the fallback runs. The async path unmaps inline; the sync path signals the retry with -EAGAIN so iaa_comp_adecompress() runs the fallback after unmapping.

Severity

9.1 (Critical)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

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{
  "affected": [],
  "aliases": [
    "CVE-2026-80945"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-11T20:19:00Z",
    "severity": "CRITICAL"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: iaa - unmap dst before software fallback on decompress\n\nOn a hardware analytics error, decompress retries through the software\nfallback, which writes req-\u003edst with the CPU while it is still mapped\nDMA_FROM_DEVICE. With SWIOTLB active the later dma_unmap_sg() copies the\nstale bounce buffer over req-\u003edst, corrupting the result.\n\nUnmap before the fallback runs. The async path unmaps inline; the sync\npath signals the retry with -EAGAIN so iaa_comp_adecompress() runs the\nfallback after unmapping.",
  "id": "GHSA-p5w3-q665-q5v8",
  "modified": "2026-09-13T09:32:09Z",
  "published": "2026-09-11T21:31:20Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-80945"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/94a25930477113730372e0fa2985da4c5ac95c9a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/fc933a4a419ba8a75da28666a018602c44846953"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/fcd86180ef78b0e41763faef7c6d2de7dfb50c1a"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-80945 (GCVE-0-2026-80945)

Vulnerability from cvelistv5 – Published: 2026-09-11 19:42 – Updated: 2026-09-13 06:28

Title

crypto: iaa - unmap dst before software fallback on decompress

Summary

In the Linux kernel, the following vulnerability has been resolved: crypto: iaa - unmap dst before software fallback on decompress On a hardware analytics error, decompress retries through the software fallback, which writes req->dst with the CPU while it is still mapped DMA_FROM_DEVICE. With SWIOTLB active the later dma_unmap_sg() copies the stale bounce buffer over req->dst, corrupting the result. Unmap before the fallback runs. The async path unmaps inline; the sync path signals the retry with -EAGAIN so iaa_comp_adecompress() runs the fallback after unmapping.

Severity

9.1 (Critical)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Assigner

Linux mitre root

References

3 references

URL	Tags
https://git.kernel.org/stable/c/fc933a4a419ba8a75…
https://git.kernel.org/stable/c/fcd86180ef78b0e41…
https://git.kernel.org/stable/c/94a25930477113730…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 2ec6761df889fdf896fde761abd447596dd8f8c2 , < fc933a4a419ba8a75da28666a018602c44846953 (git) Affected: 2ec6761df889fdf896fde761abd447596dd8f8c2 , < fcd86180ef78b0e41763faef7c6d2de7dfb50c1a (git) Affected: 2ec6761df889fdf896fde761abd447596dd8f8c2 , < 94a25930477113730372e0fa2985da4c5ac95c9a (git)
Linux	Linux	Affected: 6.8 Unaffected: 0 , < 6.8 (semver) Unaffected: 6.18.51 , ≤ 6.18.* (semver) Unaffected: 7.2.4 , ≤ 7.2.* (semver) Unaffected: 7.3-rc1 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/crypto/intel/iaa/iaa_crypto_main.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "fc933a4a419ba8a75da28666a018602c44846953",
              "status": "affected",
              "version": "2ec6761df889fdf896fde761abd447596dd8f8c2",
              "versionType": "git"
            },
            {
              "lessThan": "fcd86180ef78b0e41763faef7c6d2de7dfb50c1a",
              "status": "affected",
              "version": "2ec6761df889fdf896fde761abd447596dd8f8c2",
              "versionType": "git"
            },
            {
              "lessThan": "94a25930477113730372e0fa2985da4c5ac95c9a",
              "status": "affected",
              "version": "2ec6761df889fdf896fde761abd447596dd8f8c2",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/crypto/intel/iaa/iaa_crypto_main.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.8"
            },
            {
              "lessThan": "6.8",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.51",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3-rc1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.51",
                  "versionStartIncluding": "6.8",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2.4",
                  "versionStartIncluding": "6.8",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3-rc1",
                  "versionStartIncluding": "6.8",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: iaa - unmap dst before software fallback on decompress\n\nOn a hardware analytics error, decompress retries through the software\nfallback, which writes req-\u003edst with the CPU while it is still mapped\nDMA_FROM_DEVICE. With SWIOTLB active the later dma_unmap_sg() copies the\nstale bounce buffer over req-\u003edst, corrupting the result.\n\nUnmap before the fallback runs. The async path unmaps inline; the sync\npath signals the retry with -EAGAIN so iaa_comp_adecompress() runs the\nfallback after unmapping."
        }
      ],
      "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:H/A:N",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - iaa_crypto registers cra_name \"deflate\" at priority 300, so IPComp\u0027s crypto_alloc_acomp(\"deflate\") selects deflate-iaa. Inbound packets reach iaa_comp_adecompress via xfrm_input \u2192 ipcomp_input \u2192 crypto_acomp_decompress, so a remote IPsec/IPComp peer can trigger the bug.\nAC:L - The peer fully controls the compressed payload and can send non-IAA/invalid deflate that deterministically returns IAA_ANALYTICS_ERROR and takes the software fallback. SWIOTLB bounce, which makes dma_unmap_sg overwrite dest, is a normal IAA deployment (legacy/no-IOMMU or TDX), not an attacker-uncontrolled race.\nPR:N - The IPComp receive path decompresses packets that match an installed SA with no local account or capability check. IAA workqueue and xfrm SA setup are deployment preconditions, not attacker privileges, matching other IPComp/IAA scores in this CNA.\nUI:N - No victim action is required; attacker-sent IPComp packets automatically run hardware decompress, the analytics-error fallback, and the later dma_unmap_sg copy-back.\nS:U - The stale bounce copy-back corrupts the request dest buffer inside this kernel (IPComp skb pages or zswap folios) and does not cross a VM, IOMMU, or other security-authority boundary.\nC:H - On SWIOTLB unmap of a DMA_FROM_DEVICE dest, the bounce slot is copied over req-\u003edst. Those slots retain leftover bytes from prior DMA (other zswap pages, packets, or devices), disclosing that data into the decompressed output at dest size (a page up to the IPComp scratch, tens of KB).\nI:H - Software fallback first writes the correct plaintext, then dma_unmap_sg silently replaces it with bounce contents. The kernel then treats that leftover DMA data as the decompressed result, injecting it into the post-auth IPComp inner-packet path or into zswap-restored pages.\nA:N - The fallback returns success and the defect is silent dest corruption; it does not oops, panic, hang, deadlock, or leak allocations, so there is no availability impact beyond the integrity loss."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-13T06:28:21.316Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/fc933a4a419ba8a75da28666a018602c44846953"
        },
        {
          "url": "https://git.kernel.org/stable/c/fcd86180ef78b0e41763faef7c6d2de7dfb50c1a"
        },
        {
          "url": "https://git.kernel.org/stable/c/94a25930477113730372e0fa2985da4c5ac95c9a"
        }
      ],
      "title": "crypto: iaa - unmap dst before software fallback on decompress",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-80945",
    "datePublished": "2026-09-11T19:42:16.824Z",
    "dateReserved": "2026-08-26T14:34:25.803Z",
    "dateUpdated": "2026-09-13T06:28:21.316Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

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GHSA-P5W3-Q665-Q5V8

CVE-2026-80945 (GCVE-0-2026-80945)

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