How severe is CVE-2026-22561?

CVE-2026-22561 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-22561 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-22561?

CVE-2026-22561 affects Anthropic Claude. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-22561?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-22561 have an EU (EUVD) identifier?

Yes. CVE-2026-22561 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17476.

When was CVE-2026-22561 published?

CVE-2026-22561 was published on 2026-03-31 and last updated on 2026-06-17.

CVE-2026-22561

CVE-2026-22561 is a high-severity vulnerability in Anthropic Claude with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-427.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v4: 4.7
EPSS exploit prediction: 0% (7th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-17476
Weakness: CWE-427
Affected product: Anthropic Claude
Published: 2026-03-31
Last modified: 2026-06-17

Description

Uncontrolled search path elements in Anthropic Claude for Windows installer (Claude Setup.exe) versions prior to 1.1.3363 allow local privilege escalation via DLL search-order hijacking. The installer loads DLLs (e.g., profapi.dll) from its own directory after UAC elevation, enabling arbitrary code execution if a malicious DLL is planted alongside the installer.

Frequently asked questions

What is CVE-2026-22561?: Uncontrolled search path elements in Anthropic Claude for Windows installer (Claude Setup.exe) versions prior to 1.1.3363 allow local privilege escalation via DLL search-order hijacking. The installer loads DLLs (e.g., profapi.dll) from its own directory after UAC elevation, enabling arbitrary code execution if a malicious DLL is planted alongside the installer.
How severe is CVE-2026-22561?: CVE-2026-22561 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-22561 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-22561?: CVE-2026-22561 affects Anthropic Claude. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-22561?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-22561 have an EU (EUVD) identifier?: Yes. CVE-2026-22561 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17476.
When was CVE-2026-22561 published?: CVE-2026-22561 was published on 2026-03-31 and last updated on 2026-06-17.

References

https://trust.anthropic.com/resources?s=1cvig6ldp3zvuj1yffzr11&name=cve-2026-22561-dll-search-order-hijacking-in-claude-for-windows-installer

Affected products (1)

cpe:2.3:a:anthropic:claude:*:*:*:*:*:*:*:*

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