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Findings

CVE-2022-42916

In curl before 7.86.0, the HSTS check could be bypassed to trick it into staying with HTTP.

Published Oct 29, 2022 · updated Oct 14, 2026 · haxx curl

In curl before 7.86.0, the HSTS check could be bypassed to trick it into staying with HTTP. Using its HSTS support, curl can be instructed to use HTTPS directly (instead of using an insecure cleartext HTTP step) even when HTTP is provided in the URL. This mechanism could be bypassed if the host name in the given URL uses IDN characters that get replaced with ASCII counterparts as part of the IDN conversion, e.g., using the character UTF-8 U+3002 (IDEOGRAPHIC FULL STOP) instead of the common ASCII full stop of U+002E (.). The earliest affected version is 7.77.0 2021-05-26.

Timeline

Detection, updates, and resolution for this record.

  1. Oct 29, 2022 · NIST NVD

    Detected

    In curl before 7.86.0, the HSTS check could be bypassed to trick it into staying with HTTP. Using its HSTS support, curl can be instructed to use HTTPS directly (instead of using an insecure cleartext HTTP step) even when HTTP is provided in the URL. This mechanism could be bypassed if the host name in the given URL uses IDN characters that get replaced with ASCII counterparts as part of the IDN c

  2. Oct 14, 2026 · NIST NVD

    Updated

    In curl before 7.86.0, the HSTS check could be bypassed to trick it into staying with HTTP. Using its HSTS support, curl can be instructed to use HTTPS directly (instead of using an insecure cleartext HTTP step) even when HTTP is provided in the URL. This mechanism could be bypassed if the host name in the given URL uses IDN characters that get replaced with ASCII counterparts as part of the IDN c

Affected

  • cpe apple/macosversion unspecified
  • cpe fedoraproject/fedora35
  • cpe fedoraproject/fedora36
  • cpe fedoraproject/fedora37
  • cpe haxx/curlversion unspecified
  • cpe splunk/universal forwarderversion unspecified

Sources

  • CVE.orgCVE-2022-42916

    Official CVE identifier

    cve.org
  • FIRST EPSSCVE-2022-42916

    30-day exploitation probability 1.8%

    first.org
  • NIST NVDCVE-2022-42916

    In curl before 7.86.0, the HSTS check could be bypassed to trick it into staying with HTTP. Using its HSTS support, curl can be instructed to use HTTPS directly (instead of using an insecure cleartext HTTP step) even when HTTP is provided in the URL. This mechanism could be bypas

    nvd.nist.gov

References