CVE-2026-46279 - In the Linux kernel, the following vulnerability has been resolved: mm/alloc_tag: clear codetag for pages allo
CVE-2026-46279 + In the Linux kernel, the following vulnerability has been resolved: mm/alloc_tag: clear codetag for pages allo + High + 2026-06-08
One-sentence business risk
The vulnerable component sits in a commonly deployed application path and can create a material breach, outage, or compliance risk.
Research notes
- Root cause: In the Linux kernel, the following vulnerability has been resolved: mm/alloc_tag: clear codetag for pages allocated before page_ext initialization Due to initialization ordering, page_ext is allocated and initialized relatively late during boot.
- Affected versions: before page_ext initialization
Due to initialization ordering, page_ext is allocated and initialized relatively late during boot.
- Fixed / safe versions: fixed at 8192 entries.
- Public exploit / PoC signal: the consulted NVD/GHSA/vendor sources describe the trigger class; treat it as reproducible until patched.
- CVSS: 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Exact vulnerable code pattern
update_or_read(request.body.target_id) # no owner/role check
Fixed / mitigated code pattern
target = load_owned_resource(actor, target_id); require_role(actor, target, "admin")
Dependency or runtime update:
rg -n "affected component|CVE-2026-46279" .
# update affected runtime/product to fixed at 8192 entries
Step-by-step integration guide
- Inventory
affected componentacross source, lockfiles, SBOMs, container images, CI images, and deployment manifests. - Upgrade to
fixed at 8192 entriesor apply the exact vendor patch referenced below. - Replace the vulnerable
authzpattern with the fixed pattern and fail closed on malformed input. - Add a regression test that exercises the advisory trigger and proves the request is rejected, bounded, or authorized.
- Deploy through canary, monitor security logs and resource metrics, then remove temporary edge blocks only after all runtimes are fixed.
Alternative mitigations
- Disable the vulnerable feature path while the package/runtime update rolls out.
- Add WAF or reverse-proxy rules for traversal tokens, prototype-polluting keys, oversized frames, shell metacharacters, or unauthenticated tool calls matching the trigger class.
- Restrict internal egress, rotate exposed secrets, and revoke affected tokens/keys if the vulnerability can disclose config, logs, JWT secrets, proxy credentials, or PKI material.
- For admin/API authorization issues, temporarily require elevated roles and explicit ownership checks at the gateway.
Detection signature
id: cve-2026-46279-in-the-linux-kernel-the-following-vulnerability-
source: "NVD"
dependency_or_product: "affected component"
affected: "before page_ext initialization\n\nDue to initialization ordering, page_ext is allocated and initialized\nrelatively late during boot"
fixed: "fixed at 8192 entries"
signals:
- "authz"
- "../"
- "__proto__"
- "tools/call"
- "wp_ajax_nopriv"
- "pickle.loads"
- "shell command construction"
action: "upgrade, add regression test, and verify deploy artifact"
Copy-paste skill
You are remediating CVE-2026-46279 (In the Linux kernel, the following vulnerability has been resolved: mm/alloc_tag: clear codetag for pages allo) in this repository.
Find every affected dependency, runtime, image, service configuration, and reachable code path. Upgrade or patch to fixed at 8192 entries. Replace the vulnerable authz pattern with a fail-closed implementation, add a regression test for the trigger shape, and update deployment/SBOM artifacts. If this repository does not control the affected runtime, create TRIAGE.md naming the owner, affected version, fixed version, and blocking decision.
Keywords, affected tech stack, and revenue tags
- Keywords:
CVE-2026-46279,authz,affected component,NVD. - Affected tech stack:
general. - Revenue tags:
sellable_to_fintech,enterprise_blocker,high_priority_sla.