How severe is CVE-2026-80231?

CVE-2026-80231 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-2026-80231 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-80231?

CVE-2026-80231 affects Haxx Curl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-80231?

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.

When was CVE-2026-80231 published?

CVE-2026-80231 was published on 2026-09-06 and last updated on 2026-09-15.

CVE-2026-80231

CVE-2026-80231 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-488.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (58th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-488
Affected product: Haxx Curl
Published: 2026-09-06
Last modified: 2026-09-15

Description

A flaw in libcurl makes it wrongly reuse an existing HTTPS connection setup for a given hostname even when using a different Native CA Store setting (`CURLSSLOPT_NATIVE_CA`) than when the connection was created.

Frequently asked questions

What is CVE-2026-80231?: A flaw in libcurl makes it wrongly reuse an existing HTTPS connection setup for a given hostname even when using a different Native CA Store setting (`CURLSSLOPT_NATIVE_CA`) than when the connection was created.
How severe is CVE-2026-80231?: CVE-2026-80231 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-2026-80231 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-80231?: CVE-2026-80231 affects Haxx Curl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-80231?: 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.
When was CVE-2026-80231 published?: CVE-2026-80231 was published on 2026-09-06 and last updated on 2026-09-15.

References

Affected products (1)

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

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