During an upload, curl mishandles HTTP/2 `RST_STREAM` received from the server (with reason `HTTP_1_1_REQUIRED` or `REFUSED_STREAM`) leading to a use after free of a `struct Curl_easy` object.

The remote SUSE Linux SLED15 / SLED_SAP15 / SLES15 / SLES_SAP15 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:4954-1 advisory.

    - CVE-2026-8932: incomplete mTLS config matching in conn reuse (bsc#1268414).
    - CVE-2026-11856: cross-origin Digest auth state leak (bsc#1268426).
    - CVE-2026-18924: HTTP/2 server push UAF (bsc#1277477).
    - CVE-2026-19931: Negotiate ambient user conn reuse (bsc#1277478).
    - CVE-2026-80255: secure cookie attribute bypass with tab (bsc#1277482).
    - CVE-2026-82209: domain-scoped PSL domain cookie (bsc#1278173).
    - CVE-2026-86409: stale SigV4 headers sent unintended (bsc#1285031).
    - CVE-2026-86410: redirect to SFTP or SCP bypasses host verification (bsc#1285030).
    - CVE-2026-86414: leaking host credentials to HTTP proxy (bsc#1285026).
    - CVE-2026-87862: HSTS cache import drops longer-lived child (bsc#1285023).
    - CVE-2026-87863: HSTS response erases persisted entries (bsc#1285022).
    - CVE-2026-87864: IMAP APPEND plus CRLF conversion command injection (bsc#1285021).
    - CVE-2026-92386: server-set cookie aborts cookie jar load (bsc#1285018).
    - CVE-2026-92387: never-ending loop via server response omission (bsc#1285017).
    - CVE-2026-92388: FTP wildcard write callback mixup (bsc#1285016).
    - CVE-2026-92389: TFTP direction confusion (bsc#1285015).
    - CVE-2026-92390: -J no-clobber guarantee bypassed with 103 early hints (bsc#1285014).
    - CVE-2026-92391: curl_mime_free stack overflow by recursion (bsc#1285013).
    - CVE-2026-92392: HTTP/2 upload Use-After-Free (bsc#1285012).
    - CVE-2026-94266: password leak in CURLINFO_EFFECTIVE_URL (bsc#1285010).
    - CVE-2026-107929: local interface connection reuse mixup (bsc#1285008).

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

There are packages installed that are affected by multiple vulnerabilities referenced in the following CVEs:

  - During an upload, curl mishandles HTTP/2 `RST_STREAM` received from the server (with reason
    `HTTP_1_1_REQUIRED` or `REFUSED_STREAM`) leading to a use after free of a `struct Curl_easy` object.
    (CVE-2026-92392)

  - Setting `CURLOPT_AWS_SIGV4` to NULL but does not disable SigV4 authentication, contrary to expectations
    and documentation. A subsequent transfer on the same handle still sends an `Authorization: AWS4-HMAC-
    SHA256` header to whatever URL isset next, leaking state information. (CVE-2026-86409)

  - A flaw in the curl command line tool's logic makes it only set SSH host verification options when
    interacting directly using SFTP or SCP, and not as a result of following a redirect. (CVE-2026-86410)

  - An `ftp://` transfer configured with `CURLUSESSL_NONE` can reuse a pooled FTP control connection that a
    previous easy handle upgraded with `STARTTLS` and authenticated using a client certificate. The second
    handle performs neither a new TLS handshake nor a new FTP login, so the server continues to authorize it
    under the first handle's certificate identity. (CVE-2026-86411)

  - A remote HTTP server can set a cookie that curl accepts and writes to a Netscape cookie jar but cannot
    reload. On the next invocation using the same path for `--cookie` and `--cookie-jar`, curl fails before
    connecting, then the cleanup procedure replaces the jar with an empty file, deleting cookies for unrelated
    domains. (CVE-2026-86412)

It is, therefore, affected by a vulnerability as referenced in the ALAS2023-2026-3267 advisory.

    During an upload, curl mishandles HTTP/2 `RST_STREAM` received from the server (with reason     `HTTP_1_1_REQUIRED` or `REFUSED_STREAM`) leading to a use after free of a `struct Curl_easy` object.
    (CVE-2026-92392)

Tenable has extracted the preceding description block directly from the tested product security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The version of curl installed on the remote host is 8.12.0 prior to 8.23.0. It is, therefore, affected by a use-after-free vulnerability:

  - During an upload, curl mishandles HTTP/2 RST_STREAM received from the server (with reason     HTTP_1_1_REQUIRED or REFUSED_STREAM) leading to a use after free of a struct Curl_easy object.
    (CVE-2026-92392)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - During an upload, curl mishandles HTTP/2 `RST_STREAM` received from the server (with reason
    `HTTP_1_1_REQUIRED` or `REFUSED_STREAM`) leading to a use after free of a `struct Curl_easy` object.
    (CVE-2026-92392)

The remote Ubuntu 26.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-8927-1 advisory.

    It was discovered that curl, when built with GnuTLS support, had an out-of-bounds read in the WebSocket     send path. An attacker could possibly use this issue to obtain sensitive information. (CVE-2026-107928)

    Maksim discovered that curl did not correctly include the interface binding in connection reuse decisions     when CURLOPT_INTERFACE was used. An attacker could possibly use this issue to cause connections to go out     from an unintended source address. (CVE-2026-107929)

    Stanislav Fort discovered that curl did not properly clear AWS SigV4 authentication state when     CURLOPT_AWS_SIGV4 was set to NULL. An attacker could possibly use this issue to obtain sensitive     information. (CVE-2026-86409)

    Stanislav Fort discovered that the curl command line tool did not set SSH host verification options when     following redirects to SFTP or SCP URLs. An attacker could possibly use this issue to perform machine-in-     the-middle attacks. (CVE-2026-86410)

    Stanislav Fort discovered that curl did not properly handle cookie jar entries that could not be reloaded.
    An attacker could possibly use this issue to cause a denial of service. (CVE-2026-86412)

    Stanislav Fort discovered that an HTTP proxy could trick libcurl into sending credentials to the proxy     itself by responding to a CONNECT request with an unexpected authentication challenge. An attacker could     possibly use this issue to obtain sensitive information. (CVE-2026-86414)

    Stanislav Fort discovered that curl did not correctly handle HSTS entries when an includeSubDomains parent     entry was imported before a longer-lived child entry. An attacker could possibly use this issue to cause     curl to use unencrypted HTTP connections. (CVE-2026-87862)

    Stanislav Fort discovered that curl did not properly handle HSTS max-age values that exceeded calendar     time structure bounds. An attacker could possibly use this issue to cause a denial of service or data     loss. (CVE-2026-87863)

    Stanislav Fort discovered that curl did not properly handle IMAP APPEND commands when CURLOPT_CRLF was     enabled, allowing overflow bytes to be interpreted as pipelined commands. An authenticated attacker could     possibly use this issue to inject arbitrary IMAP commands. (CVE-2026-87864)

    Bobbeh Rhino discovered that libcurl, when used with libssh2 and a hashed known_hosts file, could     misreport a host key mismatch as a missing key. An attacker could possibly use this issue to perform     machine-in-the-middle attacks. (CVE-2026-87865)

    Joshua Rogers discovered that curl did not properly handle long cookie entries written to a Netscape     cookie jar. An attacker could possibly use this issue to cause a denial of service. (CVE-2026-92386)

    Joshua Rogers discovered that a malicious FTP, IMAP, POP3, or SMTP server could cause libcurl to block     indefinitely by omitting the final control-response line. An attacker could possibly use this issue to     cause a denial of service. (CVE-2026-92387)

    Joshua Rogers discovered that libcurl had a use-after-free vulnerability in the FTP wildcard matching     code. An attacker could possibly use this issue to cause curl to crash, resulting in a denial of service,     or execute arbitrary code. (CVE-2026-92388)

    Joshua Rogers discovered that libcurl's TFTP state machine did not properly validate transfer directions,     allowing a malicious server to force the client into transmit mode. An attacker could possibly use this     issue to obtain sensitive information. (CVE-2026-92389)

    Joshua Rogers discovered that curl did not properly enforce its file overwrite protection when using
    --remote-header-name in certain circumstances. An attacker could possibly use this issue to overwrite     local files. (CVE-2026-92390)

    Joshua Rogers discovered that curl had a stack overflow vulnerability when processing deeply nested MIME     structures. An attacker could possibly use this issue to cause curl to crash, resulting in a denial of     service. (CVE-2026-92391)

    Joshua Rogers discovered that libcurl could expose credentials in the URL returned by     CURLINFO_EFFECTIVE_URL when credentials were retrieved from a .netrc file. An attacker could possibly use     this issue to obtain sensitive information. (CVE-2026-94266)

    Joshua Rogers discovered that libcurl had a use-after-free vulnerability during HTTP/2 uploads when     handling RST_STREAM responses from the server. An attacker could possibly use this issue to cause curl to     crash, resulting in a denial of service, or execute arbitrary code. (CVE-2026-92392)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

There are packages installed that are affected by multiple vulnerabilities referenced in the following CVEs:

  - libcurl might in some circumstances reuse the wrong connection for SMB(S) transfers. libcurl features a
    pool of recent connections so that subsequent requests can reuse an existing connection to avoid overhead.
    When reusing a connection a range of criteria must be met. Due to a logical error in the code, a network
    transfer operation that was requested by an application could wrongfully reuse an existing SMB connection
    to the same server that was using a different "share" than the new subsequent transfer should. This could
    in unlucky situations lead to the download of the wrong file or the upload of a file to the wrong place.
    When this happens, the same credentials are used and the server name is the same. (CVE-2026-5773)

  - 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 performing the proper check, thus
    not noticing a possible impostor. To skip this check, the connection had to be done with QUIC with ngtcp2
    built to use GnuTLS and the user had to explicitly disable the standard certificate verification.
    (CVE-2025-13034)

  - When an OAuth2 bearer token is used for an HTTP(S) transfer, and that transfer performs a cross-protocol
    redirect to a second URL that uses an IMAP, LDAP, POP3 or SMTP scheme, curl might wrongly pass on the
    bearer token to the new target host. (CVE-2025-14524)

  - 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. This could
    make libcurl find and accept a trust chain that it otherwise would not. (CVE-2025-14819)

  - libcurl can in some circumstances reuse the wrong connection when asked to do an Negotiate-authenticated
    HTTP or HTTPS request. libcurl features a pool of recent connections so that subsequent requests can reuse
    an existing connection to avoid overhead. When reusing a connection a range of criterion must first be
    met. Due to a logical error in the code, a request that was issued by an application could wrongfully
    reuse an existing connection to the same server that was authenticated using different credentials. One
    underlying reason being that Negotiate sometimes authenticates *connections* and not *requests*, contrary
    to how HTTP is designed to work. An application that allows Negotiate authentication to a server (that
    responds wanting Negotiate) with `user1:password1` and then does another operation to the same server also
    using Negotiate but with `user2:password2` (while the previous connection is still alive) - the second
    request wrongly reused the same connection and since it then sees that the Negotiate negotiation is
    already made, it sends the request over that connection thinking it uses the user2 credentials when it is
    in fact still using the connection authenticated for user1... The set of authentication methods to use is
    set with `CURLOPT_HTTPAUTH`. Applications can disable libcurl's reuse of connections and thus mitigate
    this problem, by using one of the following libcurl options to alter how connections are or are not
    reused: `CURLOPT_FRESH_CONNECT`, `CURLOPT_MAXCONNECTS` and `CURLMOPT_MAX_HOST_CONNECTIONS` (if using the
    curl_multi API). (CVE-2026-1965)

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - During an upload, curl mishandles HTTP/2 `RST_STREAM` received from the server (with reason     `HTTP_1_1_REQUIRED` or `REFUSED_STREAM`) leading to a use after free of a `struct Curl_easy` object.
    (CVE-2026-92392)

Note that Nessus relies on the presence of the package as reported by the vendor.

The version of FreeBSD installed on the remote host is prior to tested version. It is, therefore, affected by multiple vulnerabilities as referenced in the 14dab969-c797-11f1-a6ea-8447094a420f advisory.

    The Curl project reports:

Tenable has extracted the preceding description block directly from the FreeBSD security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Debian 13 host has packages installed that are affected by multiple vulnerabilities as referenced in the dsa-6558 advisory.

    - -------------------------------------------------------------------------     Debian Security Advisory DSA-6558-1                   security@debian.org     https://www.debian.org/security/                     Salvatore Bonaccorso     October 14, 2026                      https://www.debian.org/security/faq
    - -------------------------------------------------------------------------

    Package        : curl     CVE ID         : CVE-2026-92392

    It was discovered that the cURL URL transfer library, is prone to a     use-after-free vulnerability when handling a HTTP/2 RST_STREAM received     by a server during an upload, which could result in remote code     execution.

    For the stable distribution (trixie), this problem has been fixed in     version 8.14.1-2+deb13u7. The update additionally contains fixes for     CVE-2026-8286, CVE-2026-8924 and CVE-2026-8927 which were planned to be     released with the trixie 13.8 point release.

    We recommend that you upgrade your curl packages.

    For the detailed security status of curl please refer to its security     tracker page at:
    https://security-tracker.debian.org/tracker/curl

    Further information about Debian Security Advisories, how to apply     these updates to your system and frequently asked questions can be     found at: https://www.debian.org/security/

    Mailing list: debian-security-announce@lists.debian.org

Tenable has extracted the preceding description block directly from the Debian security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Type	Severity
375384	SUSE SLED15 / SLES15 Security Update : curl (SUSE-SU-2026:4954-1)	Nessus	SuSE Local Security Checks	Local	critical
477458	Alpine: libcurl, multiple curl packages: security update to 8.23.0-r0	Tenable Cloud Security	Alpine Linux Local Security Checks	Local	critical
477458	Alpine: libcurl, multiple curl packages: security update to 8.23.0-r0	Tenable Self-Hosted Container Security	Alpine Linux Local Security Checks	Local	critical
371899	Amazon Linux 2023 : curl, curl-minimal, libcurl (ALAS2023-2026-3267)	Nessus	Amazon Linux Local Security Checks	Local	high
371160	Curl 8.12.0 < 8.23.0 HTTP/2 Upload Use-After-Free	Nessus	Misc.	Local	high
476396	Chainguard: libcurl-openssl4, multiple curl packages: security update to 8.23.0-r0	Tenable Cloud Security	Chainguard Local Security Checks	Local	high
476396	Chainguard: libcurl-openssl4, multiple curl packages: security update to 8.23.0-r0	Tenable Self-Hosted Container Security	Chainguard Local Security Checks	Local	high
367202	Ubuntu 26.04 LTS : curl vulnerabilities (USN-8927-1)	Nessus	Ubuntu Local Security Checks	Local	critical
476155	Alpine: curl: security update to 8.14.1-r4	Tenable Cloud Security	Alpine Linux Local Security Checks	Local	high
476155	Alpine: curl: security update to 8.14.1-r4	Tenable Self-Hosted Container Security	Alpine Linux Local Security Checks	Local	high
476153	Alpine: curl: security update to 8.14.1-r3	Tenable Cloud Security	Alpine Linux Local Security Checks	Local	high
476153	Alpine: curl: security update to 8.14.1-r3	Tenable Self-Hosted Container Security	Alpine Linux Local Security Checks	Local	high
365707	Linux Distros Unpatched Vulnerability : CVE-2026-92392	Nessus	Misc.	Local	high
365567	FreeBSD : Curl -- Multiple vulnerabilities (14dab969-c797-11f1-a6ea-8447094a420f)	Nessus	FreeBSD Local Security Checks	Local	critical
365528	Debian dsa-6558 : curl - security update	Nessus	Debian Local Security Checks	Local	critical

Detections

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CVE-2026-92392

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Tenable Plugins

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