Insertion of Sensitive Information Into Sent Data

Overview Affected versions of this package are vulnerable to Insertion of Sensitive Information Into Sent Data due to the improper clearing of the CURLOPTREFERER option. An attacker can cause sensitive information to be disclosed by forcing the reuse and transmission of a previous referer header ...

Use After Free

Overview Affected versions of this package are vulnerable to Use After Free in the CURLMOPTSOCKETFUNCTION callback when curleasypause is called. An attacker can execute arbitrary code or cause a denial of service by triggering the use of a dangling pointer after memory has been freed. Remediation...

Improper Verification of Cryptographic Signature

Overview Affected versions of this package are vulnerable to Improper Verification of Cryptographic Signature via the cookie parsing process. An attacker can cause unauthorized cookies to be set and transmitted to unrelated third-party domains by crafting HTTP responses that exploit improper doma...

Insufficiently Protected Credentials

Overview Affected versions of this package are vulnerable to Insufficiently Protected Credentials in the process that handles .netrc credential retrieval when a URL is specified with a username but without a password. An attacker can gain unauthorized access to sensitive information by exploiting...

Double Free

Overview Affected versions of this package are vulnerable to Double Free in the GSASL context cleanup process. An attacker can cause arbitrary code execution or a denial of service by triggering the double-free condition. Remediation Upgrade libcurl to version 8.21.0 or higher. References - Curl...

Improper Certificate Validation

Overview Affected versions of this package are vulnerable to Improper Certificate Validation when the CURLOPTSSLSESSIONIDCACHE is enabled and the CURLSSLOPTEARLYDATA option is set in CURLOPTSSLOPTIONS. An attacker can intercept and obtain sensitive information by impersonating a server and...

Authentication Bypass by Primary Weakness

Overview Affected versions of this package are vulnerable to Authentication Bypass by Primary Weakness due to incomplete matching of mTLS configuration options during connection reuse in the connection process. An attacker can cause connections to be reused with incorrect client certificate...

Improper Certificate Validation

Overview Affected versions of this package are vulnerable to Improper Certificate Validation in the CURLOPTSSHKEYFUNCTION process. An attacker can intercept or manipulate data by presenting a server host key type that does not match the recorded key type in the knownhosts file, which is improperl...

Access Control Bypass

Overview Affected versions of this package are vulnerable to Access Control Bypass in the process responsible for clearing proxy authentication credentials. An attacker can gain unauthorized access to sensitive proxy credentials by leveraging subsequent transfers that reuse stale authentication...

CVE-2026-9545

In this scenario, libcurl first uses a proper HTTP/3 server for the initial transfers, and when it makes a second transfer to the same site it has been replaced by the attacker's impostor machine - without a valid certificate. When libcurl returns to the hostname the second time with a cached SSL...

CVE-2026-9547

When a libcurl-based application performs transfers via SCP:// or SFTP:// and utilizes the CURLOPTSSHKEYFUNCTION callback, it may silently accept an untrusted server. This vulnerability occurs when a server presents a host key type that does not match the specific key type already recorded for th...

CVE-2026-9079

libcurl had a flaw that when instructed to clear proxy authentication credentials which made it not do so, leaving the old credentials around to get used for subsequent transfers that should not know nor use them...

ALPINE-CVE-2026-8927

When reusing a libcurl handle for sequential transfers driven by environment-variable proxy configuration, libcurl fails to clear the proxy authentication state between requests. Specifically, if the initial transfer authenticates against proxyA using Digest auth, a subsequent transfer routed...

ALPINE-CVE-2026-9545

In this scenario, libcurl first uses a proper HTTP/3 server for the initial transfers, and when it makes a second transfer to the same site it has been replaced by the attacker's impostor machine - without a valid certificate. When libcurl returns to the hostname the second time with a cached SSL...

ALPINE-CVE-2026-9080

Calling curleasypause within the event-based CURLMOPTSOCKETFUNCTION callback triggers a use-after-free vulnerability, where libcurl attempts to store a flag using a dangling struct pointer immediately after that pointer's memory has been freed...

ALPINE-CVE-2026-9079

libcurl had a flaw that when instructed to clear proxy authentication credentials which made it not do so, leaving the old credentials around to get used for subsequent transfers that should not know nor use them...

CVE-2026-9546

A vulnerability in libcurl caused the HTTP Referer: header to persist even when explicitly cleared. While the documentation states that passing NULL to CURLOPTREFERER suppresses the header, the option failed to clear the internal state. As a result the previous referrer string was erroneously...

ALPINE-CVE-2026-8932

libcurl would reuse a previously created connection even when some mTLS config related option had been changed that should have prohibited reuse. libcurl keeps previously used connections in a connection pool for subsequent transfers to reuse if one of them matches the setup. However, some TLS...

ALPINE-CVE-2026-9546

A vulnerability in libcurl caused the HTTP Referer: header to persist even when explicitly cleared. While the documentation states that passing NULL to CURLOPTREFERER suppresses the header, the option failed to clear the internal state. As a result the previous referrer string was erroneously...

ALPINE-CVE-2026-9547

When a libcurl-based application performs transfers via SCP:// or SFTP:// and utilizes the CURLOPTSSHKEYFUNCTION callback, it may silently accept an untrusted server. This vulnerability occurs when a server presents a host key type that does not match the specific key type already recorded for th...