JLSEC-2026-386

An insufficiently protected credentials vulnerability exists in curl 4.9 to and include curl 7.82.0 are affected that could allow an attacker to extract credentials when follows HTTPS redirects is used with authentication could leak credentials to other services that exist on different protocols ...

JLSEC-2026-420 When asked to use a `.netrc` file for credentials **and** to follow HTTP redirects, curl could leak...

When asked to use a .netrc file for credentials and to follow HTTP redirects, curl could leak the password used for the first host to the followed-to host under certain circumstances. This flaw only manifests itself if the netrc file has a default entry that omits both login and password. A rare...

JLSEC-2026-398

curl before 7.86.0 has a double free. If curl is told to use an HTTP proxy for a transfer with a non-HTTPS URL, it sets up the connection to the remote server by issuing a CONNECT request to the proxy, and then tunnels the rest of the protocol through. An HTTP proxy might refuse this request HTTP...

JLSEC-2026-423 curl's websocket code did not update the 32 bit mask pattern for each new outgoing frame as the...

curl's websocket code did not update the 32 bit mask pattern for each new outgoing frame as the specification says. Instead it used a fixed mask that persisted and was used throughout the entire connection. A predictable mask pattern allows for a malicious server to induce traffic between the two...

JLSEC-2026-430 When doing SSH-based transfers using either SCP or SFTP, and setting the `known_hosts` file, libcurl...

When doing SSH-based transfers using either SCP or SFTP, and setting the knownhosts file, libcurl could still mistakenly accept connecting to hosts not present in the specified file if they were added as recognized in the libssh global knownhosts file...

JLSEC-2026-408

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 and siglongjmp. When doi...

JLSEC-2026-437 When an OAuth2 bearer token is used for an HTTP(S) transfer, and that transfer performs a redirect...

When an OAuth2 bearer token is used for an HTTPS transfer, and that transfer performs a redirect to a second URL, curl could leak that token to the second hostname under some circumstances. If the hostname that the first request is redirected to has information in the used .netrc file, with eithe...

JLSEC-2026-403

A cleartext transmission of sensitive information vulnerability exists in curl v7.88.0 that could cause HSTS functionality to behave incorrectly when multiple URLs are requested in parallel. Using its HSTS support, curl can be instructed to use HTTPS instead of using an insecure clear-text HTTP...

JLSEC-2026-405

A vulnerability in input validation exists in curl 8.0 during communication using the TELNET protocol may allow an attacker to pass on maliciously crafted user name and "telnet options" during server negotiation. The lack of proper input scrubbing allows an attacker to send content or perform...

JLSEC-2026-389

The curl URL parser wrongly accepts percent-encoded URL separators like '/'when decoding the host name part of a URL, making it a different URL usingthe wrong host name when it is later retrieved.For example, a URL like http://example.com%2F127.0.0.1/, would be allowed bythe parser and get...

JLSEC-2026-406

A path traversal vulnerability exists in curl 8.0.0 SFTP implementation causes the tilde character to be wrongly replaced when used as a prefix in the first path element, in addition to its intended use as the first element to indicate a path relative to the user's home directory. Attackers can...

JLSEC-2026-397

When curl is used to retrieve and parse cookies from a HTTPS server, itaccepts cookies using control codes that when later are sent back to a HTTPserver might make the server return 400 responses. Effectively allowing a"sister site" to deny service to all siblings...

JLSEC-2026-402

A cleartext transmission of sensitive information vulnerability exists in curl v7.88.0 that could cause HSTS functionality fail when multiple URLs are requested serially. Using its HSTS support, curl can be instructed to use HTTPS instead of usingan insecure clear-text HTTP step even when HTTP is...

JLSEC-2026-394

When curl 7.84.0 saves cookies, alt-svc and hsts data to local files, it makes the operation atomic by finalizing the operation with a rename from a temporary name to the final target file name.In that rename operation, it might accidentally widen the permissions for the target file, leaving the...

JLSEC-2026-429 When doing TLS related transfers with reused easy or multi handles and altering the...

When doing TLS related transfers with reused easy or multi handles and altering the CURLSSLOPTNOPARTIALCHAIN 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. This could make libcur...

CLSA-2026-1777878036 curl: Fix of 2 CVEs

CVE-2019-5436: tftp: use the current blksize for recvfrom - CVE-2016-8615: cookie: replace use of fgets with custom version...

OPENSUSE-SU-2026:10674-1 curl-8.20.0-1.1 on GA media

These are all security issues fixed in the curl-8.20.0-1.1 package on the GA media of openSUSE Tumbleweed...

curl: wcurl treats some URL operands after -- as curl options

I found that wcurl does not always keep operands after -- in a pure URL-data context. The documented way to pass curl options through wcurl is --curl-options, but a value supplied as a URL operand can still reach the final curl command as an option, for example wcurl -- "--url=file:///...". A...

Moderate: Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update

An update for Red Hat Hardened Images RPMs is now available. This update includes the following RPMs: curl: curl-8.20.0-0.1.hum1 aarch64, x8664 libcurl-8.20.0-0.1.hum1 aarch64, x8664 libcurl-devel-8.20.0-0.1.hum1 aarch64, x8664 libcurl-minimal-8.20.0-0.1.hum1 aarch64, x8664 curl-8.20.0-0.1.hum1.s...

curl: curl: Proxy credential disclosure via redirects to unauthenticated proxies

A flaw was found in curl. When curl is configured to use distinct proxies for different URL schemes, a redirect from a URL using an authenticated proxy to one using an unauthenticated proxy can inadvertently expose the initial proxy's credentials. This improper credential management CWE-522 may...