Libcurl
by Curl
Source repositories
CVEs (125)
| CVE | Vendor / Product | Sev | Risk | CVSS | EPSS | KEV | Published | Description |
|---|---|---|---|---|---|---|---|---|
| CVE-2023-28320 | Med | 0.39 | 5.9 | 0.03 | May 26, 2023 | A denial of service vulnerability exists in curl <v8.1.0 in the way libcurl provides several different backends for resolving host names, selected at build time. If it is built to use the synchronous resolver, it allows name resolves to time-out slow operations using `alarm()`… | ||
| CVE-2025-13034 | Med | 0.38 | 5.9 | 0.00 | Jan 8, 2026 | When using `CURLOPT_PINNEDPUBLICKEY` option with libcurl or `--pinnedpubkey` with the curl tool, curl should check the public key of the server certificate to verify the peer. This check was skipped in a certain condition that would then make curl allow the connection without… | ||
| CVE-2024-32928 | Med | 0.38 | 5.9 | 0.00 | Aug 19, 2024 | The libcurl CURLOPT_SSL_VERIFYPEER option was disabled on a subset of requests made by Nest production devices which enabled a potential man-in-the-middle attack on requests to Google cloud services by any host the traffic was routed through. | ||
| CVE-2023-27537 | Med | 0.38 | 5.9 | 0.02 | Mar 30, 2023 | A double free vulnerability exists in libcurl <8.0.0 when sharing HSTS data between separate "handles". This sharing was introduced without considerations for do this sharing across separate threads but there was no indication of this fact in the documentation. Due to missing… | ||
| CVE-2023-27536 | Med | 0.38 | 5.9 | 0.02 | Mar 30, 2023 | An authentication bypass vulnerability exists libcurl <8.0.0 in the connection reuse feature which can reuse previously established connections with incorrect user permissions due to a failure to check for changes in the CURLOPT_GSSAPI_DELEGATION option. This vulnerability… | ||
| CVE-2023-27535 | Med | 0.38 | 5.9 | 0.02 | Mar 30, 2023 | An authentication bypass vulnerability exists in libcurl <8.0.0 in the FTP connection reuse feature that can result in wrong credentials being used during subsequent transfers. Previously created connections are kept in a connection pool for reuse if they match the current… | ||
| CVE-2024-7264 | Med | 0.37 | 6.5 | 0.17 | Jul 31, 2024 | libcurl's ASN1 parser code has the `GTime2str()` function, used for parsing an ASN.1 Generalized Time field. If given an syntactically incorrect field, the parser might end up using -1 for the length of the *time fraction*, leading to a `strlen()` getting performed on a pointer… | ||
| CVE-2023-27538 | Med | 0.36 | 5.5 | 0.01 | Mar 30, 2023 | An authentication bypass vulnerability exists in libcurl prior to v8.0.0 where it reuses a previously established SSH connection despite the fact that an SSH option was modified, which should have prevented reuse. libcurl maintains a pool of previously used connections to reuse… | ||
| CVE-2026-8458 | Med | 0.35 | 6.5 | 0.00 | Jul 3, 2026 | libcurl might in some circumstances reuse the wrong connection when asked to do Negotiate-authenticated ones, even when they are set to use different "services". libcurl features a pool of recent connections so that subsequent requests can reuse an existing connection to avoid… | ||
| CVE-2026-5545 | Med | 0.35 | 6.5 | 0.00 | May 13, 2026 | libcurl might in some circumstances reuse the wrong connection when asked to do an authenticated HTTP(S) request after a Negotiate-authenticated one, when both use the same host. libcurl features a pool of recent connections so that subsequent requests can reuse an existing… | ||
| CVE-2024-2466 | Med | 0.35 | 6.5 | 0.01 | Mar 27, 2024 | libcurl did not check the server certificate of TLS connections done to a host specified as an IP address, when built to use mbedTLS. libcurl would wrongly avoid using the set hostname function when the specified hostname was given as an IP address, therefore completely… | ||
| CVE-2022-27779 | Med | 0.35 | 5.3 | 0.03 | Jun 2, 2022 | libcurl wrongly allows cookies to be set for Top Level Domains (TLDs) if thehost name is provided with a trailing dot.curl can be told to receive and send cookies. curl's "cookie engine" can bebuilt with or without [Public Suffix List](https://publicsuffix.org/)awareness. If PSL… | ||
| CVE-2021-22876 | Med | 0.35 | 5.3 | 0.05 | Apr 1, 2021 | curl 7.1.1 to and including 7.75.0 is vulnerable to an "Exposure of Private Personal Information to an Unauthorized Actor" by leaking credentials in the HTTP Referer: header. libcurl does not strip off user credentials from the URL when automatically populating the Referer: HTTP… | ||
| CVE-2017-9502 | Med | 0.35 | 5.3 | 0.03 | Jun 14, 2017 | In curl before 7.54.1 on Windows and DOS, libcurl's default protocol function, which is the logic that allows an application to set which protocol libcurl should attempt to use when given a URL without a scheme part, had a flaw that could lead to it overwriting a heap based… | ||
| CVE-2016-3739 | Med | 0.35 | 5.3 | 0.07 | May 20, 2016 | The (1) mbed_connect_step1 function in lib/vtls/mbedtls.c and (2) polarssl_connect_step1 function in lib/vtls/polarssl.c in cURL and libcurl before 7.49.0, when using SSLv3 or making a TLS connection to a URL that uses a numerical IP address, allow remote attackers to spoof… | ||
| CVE-2025-14017 | Med | 0.34 | 6.3 | 0.00 | Jan 8, 2026 | When doing multi-threaded LDAPS transfers (LDAP over TLS) with libcurl, changing TLS options in one thread would inadvertently change them globally and therefore possibly also affect other concurrently setup transfers. Disabling certificate verification for a specific transfer… | ||
| CVE-2025-5025 | Med | 0.31 | 4.8 | 0.00 | May 28, 2025 | libcurl supports *pinning* of the server certificate public key for HTTPS transfers. Due to an omission, this check is not performed when connecting with QUIC for HTTP/3, when the TLS backend is wolfSSL. Documentation says the option works with wolfSSL, failing to specify that… | ||
| CVE-2017-7468 | Med | 0.31 | 4.8 | 0.02 | Jul 16, 2018 | In curl and libcurl 7.52.0 to and including 7.53.1, libcurl would attempt to resume a TLS session even if the client certificate had changed. That is unacceptable since a server by specification is allowed to skip the client certificate check on resume, and may instead use the… | ||
| CVE-2025-14819 | Med | 0.28 | 5.3 | 0.01 | Jan 8, 2026 | When doing TLS related transfers with reused easy or multi handles and altering the `CURLSSLOPT_NO_PARTIALCHAIN` option, libcurl could accidentally reuse a CA store cached in memory for which the partial chain option was reversed. Contrary to the user's wishes and expectations.… | ||
| CVE-2024-6874 | Med | 0.28 | 4.3 | 0.01 | Jul 24, 2024 | libcurl's URL API function [curl_url_get()](https://curl.se/libcurl/c/curl_url_get.html) offers punycode conversions, to and from IDN. Asking to convert a name that is exactly 256 bytes, libcurl ends up reading outside of a stack based buffer when built to use the *macidn* IDN… |
- risk 0.39cvss 5.9epss 0.03
A denial of service vulnerability exists in curl <v8.1.0 in the way libcurl provides several different backends for resolving host names, selected at build time. If it is built to use the synchronous resolver, it allows name resolves to time-out slow operations using `alarm()`…
- risk 0.38cvss 5.9epss 0.00
When using `CURLOPT_PINNEDPUBLICKEY` option with libcurl or `--pinnedpubkey` with the curl tool, curl should check the public key of the server certificate to verify the peer. This check was skipped in a certain condition that would then make curl allow the connection without…
- risk 0.38cvss 5.9epss 0.00
The libcurl CURLOPT_SSL_VERIFYPEER option was disabled on a subset of requests made by Nest production devices which enabled a potential man-in-the-middle attack on requests to Google cloud services by any host the traffic was routed through.
- risk 0.38cvss 5.9epss 0.02
A double free vulnerability exists in libcurl <8.0.0 when sharing HSTS data between separate "handles". This sharing was introduced without considerations for do this sharing across separate threads but there was no indication of this fact in the documentation. Due to missing…
- risk 0.38cvss 5.9epss 0.02
An authentication bypass vulnerability exists libcurl <8.0.0 in the connection reuse feature which can reuse previously established connections with incorrect user permissions due to a failure to check for changes in the CURLOPT_GSSAPI_DELEGATION option. This vulnerability…
- risk 0.38cvss 5.9epss 0.02
An authentication bypass vulnerability exists in libcurl <8.0.0 in the FTP connection reuse feature that can result in wrong credentials being used during subsequent transfers. Previously created connections are kept in a connection pool for reuse if they match the current…
- risk 0.37cvss 6.5epss 0.17
libcurl's ASN1 parser code has the `GTime2str()` function, used for parsing an ASN.1 Generalized Time field. If given an syntactically incorrect field, the parser might end up using -1 for the length of the *time fraction*, leading to a `strlen()` getting performed on a pointer…
- risk 0.36cvss 5.5epss 0.01
An authentication bypass vulnerability exists in libcurl prior to v8.0.0 where it reuses a previously established SSH connection despite the fact that an SSH option was modified, which should have prevented reuse. libcurl maintains a pool of previously used connections to reuse…
- risk 0.35cvss 6.5epss 0.00
libcurl might in some circumstances reuse the wrong connection when asked to do Negotiate-authenticated ones, even when they are set to use different "services". libcurl features a pool of recent connections so that subsequent requests can reuse an existing connection to avoid…
- risk 0.35cvss 6.5epss 0.00
libcurl might in some circumstances reuse the wrong connection when asked to do an authenticated HTTP(S) request after a Negotiate-authenticated one, when both use the same host. libcurl features a pool of recent connections so that subsequent requests can reuse an existing…
- risk 0.35cvss 6.5epss 0.01
libcurl did not check the server certificate of TLS connections done to a host specified as an IP address, when built to use mbedTLS. libcurl would wrongly avoid using the set hostname function when the specified hostname was given as an IP address, therefore completely…
- risk 0.35cvss 5.3epss 0.03
libcurl wrongly allows cookies to be set for Top Level Domains (TLDs) if thehost name is provided with a trailing dot.curl can be told to receive and send cookies. curl's "cookie engine" can bebuilt with or without [Public Suffix List](https://publicsuffix.org/)awareness. If PSL…
- risk 0.35cvss 5.3epss 0.05
curl 7.1.1 to and including 7.75.0 is vulnerable to an "Exposure of Private Personal Information to an Unauthorized Actor" by leaking credentials in the HTTP Referer: header. libcurl does not strip off user credentials from the URL when automatically populating the Referer: HTTP…
- risk 0.35cvss 5.3epss 0.03
In curl before 7.54.1 on Windows and DOS, libcurl's default protocol function, which is the logic that allows an application to set which protocol libcurl should attempt to use when given a URL without a scheme part, had a flaw that could lead to it overwriting a heap based…
- risk 0.35cvss 5.3epss 0.07
The (1) mbed_connect_step1 function in lib/vtls/mbedtls.c and (2) polarssl_connect_step1 function in lib/vtls/polarssl.c in cURL and libcurl before 7.49.0, when using SSLv3 or making a TLS connection to a URL that uses a numerical IP address, allow remote attackers to spoof…
- risk 0.34cvss 6.3epss 0.00
When doing multi-threaded LDAPS transfers (LDAP over TLS) with libcurl, changing TLS options in one thread would inadvertently change them globally and therefore possibly also affect other concurrently setup transfers. Disabling certificate verification for a specific transfer…
- risk 0.31cvss 4.8epss 0.00
libcurl supports *pinning* of the server certificate public key for HTTPS transfers. Due to an omission, this check is not performed when connecting with QUIC for HTTP/3, when the TLS backend is wolfSSL. Documentation says the option works with wolfSSL, failing to specify that…
- risk 0.31cvss 4.8epss 0.02
In curl and libcurl 7.52.0 to and including 7.53.1, libcurl would attempt to resume a TLS session even if the client certificate had changed. That is unacceptable since a server by specification is allowed to skip the client certificate check on resume, and may instead use the…
- risk 0.28cvss 5.3epss 0.01
When doing TLS related transfers with reused easy or multi handles and altering the `CURLSSLOPT_NO_PARTIALCHAIN` option, libcurl could accidentally reuse a CA store cached in memory for which the partial chain option was reversed. Contrary to the user's wishes and expectations.…
- risk 0.28cvss 4.3epss 0.01
libcurl's URL API function [curl_url_get()](https://curl.se/libcurl/c/curl_url_get.html) offers punycode conversions, to and from IDN. Asking to convert a name that is exactly 256 bytes, libcurl ends up reading outside of a stack based buffer when built to use the *macidn* IDN…
Page 4 of 7