CVE-2026-98134

Что произошло

In the Linux kernel, the following vulnerability has been resolved: bpf: check_cond_jmp_op(): properly infer if register is null Nicholas Carlini reported a bug when verifier can incorrectly infer that a pointer is non-null. The bug occurs when two pointers are compared and one of them has a type w/o PTR_MAYBE_NULL flag, but which allows a value to be NULL at runtime. Here is an example: // `a` is PTR_TO_MEM | MEM_RDONLY | PTR_UNTRUSTED // `a` is 0 at runtime. // `b` is PTR_TO_MAP_VALUE | PTR_MAYBE_NULL void *a = bpf_rdonly_cast(0, 0); int *b = bpf_map_lookup_elem(...); if (a == b) *b = 42; // verifier does not catch null pointer dereference This happens because of a special case in check_cond_jmp_op(), which attempts to strip PTR_MAYBE_NULL flags from pointer types, when processing comparisons like `rA == rB`, if either rA or rB can't be null. The non-null property is derived based on the absence of PTR_MAYBE_NULL flag on rA's or rB's type. But that is not sufficient for types like PTR_TO_MEM, as in the example. This patch replaces type_may_be_null() call with reg_not_null(), which contains an allowlist of types for which absence of PTR_MAYBE_NULL actually means that the value can't be NULL at runtime. At the moment, the list in the reg_not_null() omits two types for which PTR_MAYBE_NULL is applicable: PTR_TO_XDP_SOCK and PTR_TO_BUF. In order to remain backward compatible, and assuming that only comparison between pointers of the same type makes sense, this commit extends reg_not_null(). W/o such an extension e.g. verifier_jeq_infer_not_null/null_ptr_to_map_value fails. reg_not_null() can be extended further, but I deem that out of scope for the fix at hand. Explicit base_type(...) != PTR_TO_BTF_ID checks in the check_cond_jmp_op() can be removed with migration to reg_not_null(), but that is a behavioural change, as the special case would start matching for PTR_TO_BTF_ID that is also is_trusted_reg(). I omit the behavioural change from this commit.

Что делать

dpkg-query -W -f='${Package}	${Version}\n'

rpm -qa --qf '%{NAME}\t%{VERSION}-%{RELEASE}\n'

Get-HotFix | Select-Object HotFixID, InstalledOn

Продукты и затронутые версии

{
  "status": "affected",
  "version": "befae75856ab406a3f3fab2aa2118cf3b2dfe3e6",
  "lessThan": "d51cd486930f5bcfd4b55d55ab8e47b03f93d2ed",
  "versionType": "git"
}

{
  "status": "affected",
  "version": "befae75856ab406a3f3fab2aa2118cf3b2dfe3e6",
  "lessThan": "dfd8f8adda565e08c370c45cf9d6b2511ba9b5c6",
  "versionType": "git"
}

{
  "status": "affected",
  "version": "befae75856ab406a3f3fab2aa2118cf3b2dfe3e6",
  "lessThan": "9bf96b4347f541604b3caadeabda0773d9ceaf2a",
  "versionType": "git"
}

{
  "status": "affected",
  "version": "befae75856ab406a3f3fab2aa2118cf3b2dfe3e6",
  "lessThan": "b55c9f019e169ed0d01394f96e172286a8b21b99",
  "versionType": "git"
}

{
  "status": "affected",
  "version": "befae75856ab406a3f3fab2aa2118cf3b2dfe3e6",
  "lessThan": "d3ef6c097ba078e1f8c7239d76a0ce8b61e75095",
  "versionType": "git"
}

{
  "status": "affected",
  "version": "6.2"
}

{
  "status": "unaffected",
  "version": "0",
  "lessThan": "6.2",
  "versionType": "semver"
}

{
  "status": "unaffected",
  "version": "6.6.160",
  "versionType": "semver",
  "lessThanOrEqual": "6.6.*"
}

{
  "status": "unaffected",
  "version": "6.12.114",
  "versionType": "semver",
  "lessThanOrEqual": "6.12.*"
}

{
  "status": "unaffected",
  "version": "6.18.57",
  "versionType": "semver",
  "lessThanOrEqual": "6.18.*"
}

{
  "status": "unaffected",
  "version": "7.2.7",
  "versionType": "semver",
  "lessThanOrEqual": "7.2.*"
}

{
  "status": "unaffected",
  "version": "7.3",
  "versionType": "original_commit_for_fix",
  "lessThanOrEqual": "*"
}

CVSS: оценки и векторы

Оценка CVSS отсутствует.

Источники и ссылки

{
  "cwes": [],
  "epss": {
    "source": "epss",
    "received_at": "2026-11-02T21:15:46.177110+00:00"
  },
  "title": {
    "source": "cve",
    "received_at": "2026-10-28T20:15:08.218789+00:00"
  },
  "scores": [],
  "status": {
    "source": "cve",
    "received_at": "2026-10-28T20:15:08.218789+00:00"
  },
  "affected": [
    "cve"
  ],
  "published": {
    "source": "cve",
    "received_at": "2026-10-28T20:15:08.218789+00:00"
  },
  "solutions": [],
  "percentile": {
    "source": "epss",
    "received_at": "2026-11-02T21:15:46.177110+00:00"
  },
  "references": [
    "cve"
  ],
  "description": {
    "source": "cve",
    "received_at": "2026-10-28T20:15:08.218789+00:00"
  },
  "workarounds": [],
  "configurations": []
}

Хронология записи

1. Данные обновлены03.11.2026, 00:15
2. Данные обновлены02.11.2026, 00:13
3. Данные обновлены31.10.2026, 12:00
4. Данные обновлены29.10.2026, 12:47
5. Опубликована28.10.2026, 23:15

Личная заметка и статус

Другие CVE того же продукта