CVE-2021-22897

curl: Cipher settings shared for all connections when using schannel TLS backed

Published Jun 11, 2021 CVSS 3.1 · 5.3 Medium EPSS 4.3% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

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History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
hackerone
Published
Updated
Oct 14, 2026, 10:21 AM
Reserved
Jan 6, 2021, 12:00 AM
Status
Modified
Published
Jun 11, 2021, 4:15 PM
Modified
Oct 14, 2026, 11:16 AM
Severity
Low
Public date
May 26, 2021, 12:00 AM