How severe is CVE-2026-3805?

CVE-2026-3805 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-3805 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-3805?

CVE-2026-3805 affects Haxx Curl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-3805?

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-2026-3805 have an EU (EUVD) identifier?

Yes. CVE-2026-3805 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-11141.

When was CVE-2026-3805 published?

CVE-2026-3805 was published on 2026-03-11 and last updated on 2026-06-17.

CVE-2026-3805

CVE-2026-3805 is a high-severity vulnerability in Haxx Curl with a CVSS 3.x base score of 7.5. 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-416.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (49th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-11141
Weakness: CWE-416
Affected product: Haxx Curl
Published: 2026-03-11
Last modified: 2026-06-17

Description

When doing a second SMB request to the same host again, curl would wrongly use a data pointer pointing into already freed memory.

Frequently asked questions

What is CVE-2026-3805?: When doing a second SMB request to the same host again, curl would wrongly use a data pointer pointing into already freed memory.
How severe is CVE-2026-3805?: CVE-2026-3805 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-3805 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-3805?: CVE-2026-3805 affects Haxx Curl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-3805?: 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-2026-3805 have an EU (EUVD) identifier?: Yes. CVE-2026-3805 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-11141.
When was CVE-2026-3805 published?: CVE-2026-3805 was published on 2026-03-11 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:*

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