LiveActive security incident?Get immediate response
CVE Record

CVE-2026-46182: pseries/papr-hvpipe: Prevent kernel stack memory leak to userspace

In the Linux kernel, the following vulnerability has been resolved: pseries/papr-hvpipe: Prevent kernel stack memory leak to userspace The hdr variable is allocated on the stack and only hdr.version and hdr.flags are initialized explicitly. Because the struct papr_hvpipe_hdr contains reserved padding bytes (reserved[3] and reserved2[40]), these could leak the uninitialized bytes to userspace after copy_to_user(). This patch fixes that by initializing the whole struct to 0.

UnknownCVSS not scoredNot KEV-listedUpdated
Discuss exposureBack to CVEs
Glexia's TakeAutomated analysisunknown

Security readout for executives and security teams

Plain-English summary

CVE-2026-46182 is a Linux kernel information disclosure issue. A small kernel data structure could include uninitialized stack bytes when copied to userspace, exposing limited kernel memory contents. The source says the fix initializes the whole structure to zero.

Executive priority

Treat this as a targeted kernel information disclosure issue with incomplete severity data. It merits routine patch tracking, faster attention for Power/pseries-related Linux estates, and escalation only if vendor advisories later show broader impact or exploitation.

Technical view

The flaw is in Linux pseries/papr-hvpipe. Only hdr.version and hdr.flags were explicitly initialized, while reserved padding bytes could remain uninitialized. A later copy_to_user() could disclose those stack bytes to userspace. Stable kernel commits address this by zero-initializing struct papr_hvpipe_hdr.

Likely exposure

Exposure appears limited to affected Linux kernel versions where the pseries/papr-hvpipe path is present and reachable. The CVE record lists Linux as affected but does not provide CPEs, distribution package names, or deployment prerequisites.

Exploitation context

The provided sources do not show active exploitation, KEV listing, public exploit code, or CVSS scoring. The description supports an information leak to userspace, not remote code execution or privilege escalation by itself.

Researcher notes

Evidence is narrow but clear: uninitialized reserved fields in a stack-allocated header may be copied to userspace. The bundle lacks CVSS, CWE, CPEs, exploit prerequisites, and distro-specific fixed builds, so validation should focus on kernel lineage and patch presence.

Mitigation direction

  • Review the referenced stable kernel commits for your maintained kernel branch.
  • Apply vendor or distribution kernel updates that include the zero-initialization fix.
  • Prioritize systems running affected Linux kernel versions with pseries/PAPR usage.
  • If no vendor advisory exists, monitor Linux stable and distribution guidance.

Validation and detection

  • Inventory Linux kernel versions against the CVE affected version data.
  • Confirm whether pseries/papr-hvpipe code is built and relevant in your environment.
  • Verify deployed kernels include one of the referenced stable fixes.
  • Track distribution advisories for package-level fixed versions.
Prepared
Confidence
medium
Sources
5

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cve · low confidence lookup

CVE-2026-46182 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors
3Timeline events
0ADP providers
4Source links

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. CVE publishedCVE Program

    The CVE record was published.

  3. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
LinuxLinuxcebdb522fd3edd1fe05f7b4a74a27da7dd0f8d86, cebdb522fd3edd1fe05f7b4a74a27da7dd0f8d86, cebdb522fd3edd1fe05f7b4a74a27da7dd0f8d86unaffected
LinuxLinux6.18, 0, 6.18.30, 7.0.7, 7.1affected
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.