CVE-2018-1000007

CVE-2018-1000007 is a critical-severity vulnerability in Haxx Curl with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

libcurl 7.1 through 7.57.0 might accidentally leak authentication data to third parties. When asked to send custom headers in its HTTP requests, libcurl will send that set of headers first to the host in the initial URL but also, if asked to follow redirects and a 30X HTTP response code is returned, to the host mentioned in URL in the `Location:` response header value. Sending the same set of headers to subsequent hosts is in particular a problem for applications that pass on custom `Authorization:` headers, as this header often contains privacy sensitive information or data that could allow others to impersonate the libcurl-using client's request.

Frequently asked questions

What is CVE-2018-1000007?
libcurl 7.1 through 7.57.0 might accidentally leak authentication data to third parties. When asked to send custom headers in its HTTP requests, libcurl will send that set of headers first to the host in the initial URL but also, if asked to follow redirects and a 30X HTTP response code is returned, to the host mentioned in URL in the `Location:` response header value. Sending the same set of headers to subsequent hosts is in particular a problem for applications that pass on custom `Authorization:` headers, as this header often contains privacy sensitive information or data that could allow others to impersonate the libcurl-using client's request.
How severe is CVE-2018-1000007?
CVE-2018-1000007 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-1000007 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 8% (94th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-1000007?
CVE-2018-1000007 primarily affects Haxx Curl. In total, 20 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-1000007?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2018-1000007 published?
CVE-2018-1000007 was published on 2018-01-24 and last updated on 2026-06-17.

References

Affected products (20)

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