Vulnerability-Lookup

GHSA-MGH7-VVQ6-R2VR

Vulnerability from github – Published: 2026-09-17 18:31 – Updated: 2026-09-18 18:31

Details

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

bpf: Check pointer type for all atomic RMW paths

Atomic RMW verification records an instruction pointer type only when the current destination is PTR_TO_ARENA. A second path can therefore reach the same instruction with an ordinary pointer without comparing it against the saved arena type.

The post-verification fixup uses the saved type to rewrite the instruction to BPF_PROBE_ATOMIC for every path. Record the actual destination type for all atomic RMW paths so the existing mismatch check rejects incompatible uses of one instruction.

Severity

7.8 (High)


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

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-90177"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-17T17:17:11Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Check pointer type for all atomic RMW paths\n\nAtomic RMW verification records an instruction pointer type only when the\ncurrent destination is PTR_TO_ARENA. A second path can therefore reach the\nsame instruction with an ordinary pointer without comparing it against the\nsaved arena type.\n\nThe post-verification fixup uses the saved type to rewrite the instruction\nto BPF_PROBE_ATOMIC for every path. Record the actual destination type for\nall atomic RMW paths so the existing mismatch check rejects incompatible\nuses of one instruction.",
  "id": "GHSA-mgh7-vvq6-r2vr",
  "modified": "2026-09-18T18:31:27Z",
  "published": "2026-09-17T18:31:54Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-90177"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4bc49ae344d65cfcef738f281ac575cf73ca2fc5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/eb287c6e81dedef92da01eb947f380d0aae513c3"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-90177 (GCVE-0-2026-90177)

Vulnerability from cvelistv5 – Published: 2026-09-17 16:07 – Updated: 2026-09-18 17:53

Title

bpf: Check pointer type for all atomic RMW paths

Summary

In the Linux kernel, the following vulnerability has been resolved: bpf: Check pointer type for all atomic RMW paths Atomic RMW verification records an instruction pointer type only when the current destination is PTR_TO_ARENA. A second path can therefore reach the same instruction with an ordinary pointer without comparing it against the saved arena type. The post-verification fixup uses the saved type to rewrite the instruction to BPF_PROBE_ATOMIC for every path. Record the actual destination type for all atomic RMW paths so the existing mismatch check rejects incompatible uses of one instruction.

Severity

7.8 (High)


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

Assigner

Linux mitre root

References

2 references

URL	Tags
https://git.kernel.org/stable/c/eb287c6e81dedef92…
https://git.kernel.org/stable/c/4bc49ae344d65cfce…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: d503a04f8bc0c75dc9db9452d8cc79d748afb752 , < eb287c6e81dedef92da01eb947f380d0aae513c3 (git) Affected: d503a04f8bc0c75dc9db9452d8cc79d748afb752 , < 4bc49ae344d65cfcef738f281ac575cf73ca2fc5 (git)
Linux	Linux	Affected: 6.10 Unaffected: 0 , < 6.10 (semver) Unaffected: 7.2.6 , ≤ 7.2.* (semver) Unaffected: 7.3-rc1 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "kernel/bpf/verifier.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "eb287c6e81dedef92da01eb947f380d0aae513c3",
              "status": "affected",
              "version": "d503a04f8bc0c75dc9db9452d8cc79d748afb752",
              "versionType": "git"
            },
            {
              "lessThan": "4bc49ae344d65cfcef738f281ac575cf73ca2fc5",
              "status": "affected",
              "version": "d503a04f8bc0c75dc9db9452d8cc79d748afb752",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "kernel/bpf/verifier.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.10"
            },
            {
              "lessThan": "6.10",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.6",
              "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": "7.2.6",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3-rc1",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Check pointer type for all atomic RMW paths\n\nAtomic RMW verification records an instruction pointer type only when the\ncurrent destination is PTR_TO_ARENA. A second path can therefore reach the\nsame instruction with an ordinary pointer without comparing it against the\nsaved arena type.\n\nThe post-verification fixup uses the saved type to rewrite the instruction\nto BPF_PROBE_ATOMIC for every path. Record the actual destination type for\nall atomic RMW paths so the existing mismatch check rejects incompatible\nuses of one instruction."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The attacker-controlled input is the BPF instruction stream copied in bpf_prog_load() from bpf(2) BPF_PROG_LOAD (__sys_bpf). do_check_insn() then check_atomic() then check_atomic_rmw() sees a mixed PTR_TO_ARENA versus kernel-pointer atomic; that bytecode is local syscall input, not a remote protocol payload.\nAC:L - The attacker authors both verifier paths: one branch with a PTR_TO_ARENA destination and another with PTR_TO_MAP_VALUE or PTR_TO_STACK at the same BPF_ATOMIC RMW. check_atomic_rmw() records only the arena type, bpf_convert_ctx_accesses() rewrites it to BPF_PROBE_ATOMIC, and bpf_prog_test_run_syscall() takes the non-arena path on demand.\nPR:L - The mixed path needs a BPF_MAP_TYPE_ARENA map; check_map_prog_compatibility() rejects that unless env-\u003ebpf_capable and env-\u003eallow_ptr_leaks (bpf_token_capable(CAP_BPF) and bpf_token_capable(CAP_PERFMON)). bpf_token_capable() uses ns_capable() on a delegated token userns, so this is not init-namespace root.\nUI:N - The attacker creates the arena with BPF_MAP_CREATE, loads the mixed-path program with BPF_PROG_LOAD, and executes it via bpf_prog_test_run() to bpf_prog_test_run_syscall(); no other user must mount, open a file, or otherwise cooperate.\nS:U - The confused BPF_PROBE_ATOMIC is JITed as emit_atomic_rmw_index() adding arena kern_vm_start (R12) onto a kernel map or stack pointer and runs in the host kernel; that is host memory corruption, not a KVM/Xen guest-to-host escape or IOMMU bypass.\nC:H - After bpf_convert_ctx_accesses() rewrites the shared RMW to BPF_PROBE_ATOMIC, the non-arena path executes lock xchg/cmpxchg/fetch-add at (PTR_TO_MAP_VALUE or PTR_TO_STACK + bpf_arena_get_kern_vm_start()). BPF_FETCH, XCHG, and CMPXCHG return the old value from that address, an arbitrary kernel read.\nI:H - The same instruction performs an attacker-chosen atomic RMW (BPF_ADD/AND/OR/XOR/XCHG/CMPXCHG in check_atomic_rmw) at kernel_ptr+kern_vm_start. With CONFIG_VMAP_STACK or a vmalloc map, that sum is a canonical direct-map address, giving a kernel write primitive.\nA:H - An atomic RMW into the direct map corrupts live kernel state and can panic; a non-canonical or unmapped sum that a JIT does not cover with an exception table oopses. Type-confused kernel atomics are Availability High."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-18T17:53:37.480Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/eb287c6e81dedef92da01eb947f380d0aae513c3"
        },
        {
          "url": "https://git.kernel.org/stable/c/4bc49ae344d65cfcef738f281ac575cf73ca2fc5"
        }
      ],
      "title": "bpf: Check pointer type for all atomic RMW paths",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-90177",
    "datePublished": "2026-09-17T16:07:03.097Z",
    "dateReserved": "2026-09-11T19:38:34.791Z",
    "dateUpdated": "2026-09-18T17:53:37.480Z",
    "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.

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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

GHSA-MGH7-VVQ6-R2VR

CVE-2026-90177 (GCVE-0-2026-90177)

Tags

Sightings

Nomenclature

Related by attack behaviour