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UNPWNED
CVE Radar
MediumcURL

CVE-2021-22897

curl 7.61.0 through 7.76.1 suffers from exposure of data element to wrong session due to a mistake in the code for CURLOPT_SSL_CIPHER_LIST when libcurl is built to use the Schannel TLS library. The selected cipher set was stored in a single "static" variable in the library, which has the surprising side-effect that if an application sets up multiple concurrent transfers, the last one that sets the ciphers will accidentally control the set used by all transfers. In a worst-case scenario, this weakens transport security significantly.

CVSS Base Score
5.3

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Exploit Probability
91%EPSS PERCENTILE0100

More exploitable than 91% of all CVEs · Top 9%

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Details
Published
2021-06-11
Last modified
2026-10-14
Affected
cURL

Data from the National Vulnerability Database (NVD), CISA KEV, and FIRST.org EPSS. This product uses the NVD API but is not endorsed or certified by the NVD. EPSS is a probability estimate, not a guarantee of exploitation.