Successfully using libcurl to do a transfer to a specific HTTP origin (`hostA`) with **Digest** authentication and then changing the origin to a different one (`hostB`) for a second transfer, reusing the same handle, makes libcurl wrongly pass on the `Authorization:` header field meant for `hostA`, to `hostB`.

According to its self-reported version, the Tenable Security Center running on the remote host is prior to 6.9.0. It is, therefore, affected by multiple vulnerabilities as referenced in the TNS-2026-22 advisory.

  - 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)

  - libcurl keeps previously used connections in a connection pool for subsequent transfers to reuse if one of     them matches the setup. An easy handle that first uses default native CA trust can continue trusting the     native platform store after the application switches that same handle to custom CA material for a later     transfer. (CVE-2026-11564)

  - A command injection vulnerability exists in Security Center where a remote, unauthenticated attacker     could exploit this issue to execute arbitrary commands on the underlying operating system with the     privileges of the service account. (CVE-2026-19682)

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

An update of the curl package has been released.

The remote Fedora 43 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2026-097fb2e7e9 advisory.

    - fix cross-proxy Digest auth state leak (CVE-2026-7168)
    - fix cross-origin Digest auth state leak (CVE-2026-11856)
    - fix password leak with netrc and user in URL (CVE-2026-8926)
    - fix SSH improper host validation (CVE-2026-9547)
    - fix trailing dot domain super cookie (CVE-2026-8924)

Tenable has extracted the preceding description block directly from the Fedora 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 Fedora 44 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2026-e691fbbfe7 advisory.

    - Fix trailing dot domain super cookie (CVE-2026-8924)
    - Fix SSH improper host validation (CVE-2026-9547)
    - Fix password leak with netrc and user in URL (CVE-2026-8926)
    - Fix cross-origin Digest auth state leak (CVE-2026-11856)
    - Fix cross-proxy Digest auth state leak (CVE-2026-7168)
    - Fix OCSP stapling bypass with Apple SecTrust (CVE-2026-7009)

Tenable has extracted the preceding description block directly from the Fedora 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 version of libcurl installed on the remote host is 7.10.6 prior to 8.21.0. It is, therefore, affected by a credential disclosure vulnerability:

  - Successfully using libcurl with Digest authentication and then changing the origin to a different host     for a second transfer, reusing the same handle, makes libcurl wrongly pass on the Authorization header     meant for the first host. (CVE-2026-11856)

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

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

  - Successfully using libcurl to do a transfer to a specific HTTP origin (`hostA`) with **Digest**     authentication and then changing the origin to a different one (`hostB`) for a second transfer, reusing     the same handle, makes libcurl wrongly pass on the `Authorization:` header field meant for `hostA`, to     `hostB`. (CVE-2026-11856)

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

ID	Name	Product	Family	Type	Severity
339129	Tenable Security Center < 6.9.0 Multiple Vulnerabilities (TNS-2026-22)	Nessus	Misc.	Combined	critical
334708	Photon OS 5.0: Curl PHSA-2026-5.0-90-0951	Nessus	PhotonOS Local Security Checks	Local	critical
333276	Fedora 43 : curl (2026-097fb2e7e9)	Nessus	Fedora Local Security Checks	Local	medium
331599	Fedora 44 : curl (2026-e691fbbfe7)	Nessus	Fedora Local Security Checks	Local	medium
323007	libcurl 7.10.6 < 8.21.0 Cross-Origin Digest Auth State Leak	Nessus	Misc.	Local	critical
322463	Linux Distros Unpatched Vulnerability : CVE-2026-11856	Nessus	Misc.	Local	critical

Detections

Analytics

CVE-2026-11856

critical

Tenable Plugins

critical

critical

medium

medium

critical

critical