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CVE Record

CVE-2021-47417: libbpf: Fix memory leak in strset

In the Linux kernel, the following vulnerability has been resolved: libbpf: Fix memory leak in strset Free struct strset itself, not just its internal parts.

UnknownCVSS not scoredNot KEV-listedUpdated
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Glexia's TakeAutomated analysisunknown

Security readout for executives and security teams

Plain-English summary

CVE-2021-47417 is a Linux kernel libbpf memory leak involving the strset structure. The public record says the fix frees the strset object itself, not only its internal parts. No CVSS score, CWE, exploitation evidence, or business-impact detail is provided in the source bundle.

Executive priority

Handle through normal Linux kernel patch governance. There is not enough public evidence to justify emergency response, but affected systems should still be updated because memory leaks can create stability risk over time.

Technical view

The issue is in Linux kernel libbpf strset cleanup logic. The fix changes deallocation so struct strset is freed in addition to its internal allocations. The source lists affected Linux versions and two stable kernel commits, but does not provide exploit prerequisites, reachable code paths, or impact severity.

Likely exposure

Exposure is limited to Linux systems running affected kernel/libbpf code as identified by vendor or distro advisories. The bundle lists Linux versions around 5.13, 5.14.12, and 5.15, plus commit identifiers, but exact distro exposure requires backport verification.

Exploitation context

The source bundle does not report active exploitation, and CISA KEV status is false. No public exploit status, attacker prerequisites, or exploitation method is provided. Treat this as a patch-management and inventory validation item unless vendor guidance indicates higher urgency.

Researcher notes

Evidence is sparse: the record describes a memory leak fix but omits CVSS, CWE, exploitability, and triggering conditions. Analysis should focus on code lineage, distro backports, and whether local workloads exercise the affected libbpf strset path.

Mitigation direction

  • Check Linux distribution advisories for CVE-2021-47417 applicability.
  • Update to a kernel package containing the linked stable fix.
  • Confirm whether vendor kernels backported the libbpf strset fix.
  • Prioritize internet-facing or multi-tenant Linux systems if affected.
  • Track this under routine kernel maintenance unless vendor severity is higher.

Validation and detection

  • Inventory Linux kernel versions across servers and images.
  • Compare deployed kernels against vendor CVE advisories and fixed package versions.
  • Check whether the linked stable commits exist in your kernel source package.
  • Review asset groups using BPF/libbpf tooling or kernel observability agents.
Prepared
Confidence
medium
Sources
4

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

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CVE-2021-47417 mapping review

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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
2ADP providers
3Source links

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: noneAutomatable: noTechnical Impact: partial

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.

ADP provider summaries

CVECVE Program Container
CISA-ADPCISA ADP Vulnrichment
other:ssvc

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
LinuxLinux90d76d3ececc74bf43b2a97f178dadfa1e52be54, 90d76d3ececc74bf43b2a97f178dadfa1e52be54unaffected
LinuxLinux5.13, 0, 5.14.12, 5.15affected
Weakness

CWE details

No CWE listed

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