CVE-2026-98713 (GCVE-0-2026-98713)

Vulnerability from cvelistv5 – Published: 2026-10-18 15:46 – Updated: 2026-10-19 09:24
VLAI
Title
KVM: arm64: Apply the fine-grained UNDEFs without FEAT_FGT
Summary
In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: Apply the fine-grained UNDEFs without FEAT_FGT FGUs don't actually require hardware support, so don't gate fgt trap config insertion on FGT. This is the only action required to allow FGUs always, as kvm_calculate_traps() already computes the FGU bits with or without FEAT_FGT. This also fixes a spurious WARN when a TLBI OS is run on a guest in vEL1 without FEAT_TLBIOS on non FEAT_FGT hardware. In this configuration the course-grained HCR_EL2.TTLBOS trap reaches the handler handle_tlbi_el1(), which expects an EL1 TLBI only from vEL2. With FGUs enabled the UNDEF will be injected without needing the specific handler. [oliver: Take Wei-Lin's suggested changelog]
Severity
No CVSS data available.
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: f5a5a406b4b8bb6c1fc7a1e92a872bd86061a53f , < 2f4a15c52a552c5244ec27f4ca8bda855594f918 (git)
Affected: f5a5a406b4b8bb6c1fc7a1e92a872bd86061a53f , < 1113374a17d7f7d16b02ee0bbd9b1e7a60cbb087 (git)
Affected: f5a5a406b4b8bb6c1fc7a1e92a872bd86061a53f , < af3300b3a6bace925a496f3520e171c07b999c72 (git)
Affected: f5a5a406b4b8bb6c1fc7a1e92a872bd86061a53f , < 4bdd2b3a708c1feb701cb8b62feb8ad2fd77bb07 (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.9
Unaffected: 0 , < 6.9 (semver)
Unaffected: 6.12.113 , ≤ 6.12.* (semver)
Unaffected: 6.18.56 , ≤ 6.18.* (semver)
Unaffected: 7.2.10 , ≤ 7.2.* (semver)
Unaffected: 7.3 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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{
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          "product": "Linux",
          "programFiles": [
            "arch/arm64/kvm/emulate-nested.c"
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        }
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    "datePublished": "2026-10-18T15:46:45.902Z",
    "dateReserved": "2026-09-25T10:25:14.365Z",
    "dateUpdated": "2026-10-19T09:24:24.367Z",
    "state": "PUBLISHED"
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      "product_status:under_investigation": "1",
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          }
        ],
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        "metrics": {},
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      "source": "Red Hat CSAF VEX",
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      "title": "kernel: KVM: arm64: Apply the fine-grained UNDEFs without FEAT_FGT",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98713.json",
      "version": "3"
    }
  }
}



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