Authentication bypass in sshd-core in Apache MINA SSHD versions 2.0.0 to 2.19.0 and 3.0.0-M1 to 3.0.0-M5 for a certain (presumed rare) way to implement an SSH server. Apache MINA SSHD is a Java library for client- and server-side SSH. In the server part of the library, a mechanism to perform "asynchronous authentication" exists. A server implemented with Apache MINA SSHD must contain explicit code to make use of this feature. The implementation of this feature was flawed and could potentially lead to skipping checking the signature in public-key or hostbased authentication, or returning a wrong result. Users are recommended to upgrade to Apache MINA SSHD 2.20.0 or 3.0.0-M6, which fix the logic error and which additionally forbid the use of this "asynchronous authentication" mechanism with the public-key or hostbased authentication schemes: if used, the SSH session will be closed and the server will log an entry indicating that asynchronous authentication may be used only with password or keyboard-interactive authentication.

The remote Redhat Enterprise Linux 10 / 8 / 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2026:99018 advisory.

    Red Hat JBoss Enterprise Application Platform 8 is a platform for Java     applications based on the WildFly application runtime.

    This asynchronous patch is an update for Red Hat JBoss Enterprise Application     Platform 8.1. See Release Notes for information about the most significant bug     fixes and enhancements included in this release.

    Security Fix(es):

    * bcjmail-jdk18on: Bouncy Castle for Java: Integrity compromise due to insufficient tag-length enforcement     in CMS AuthEnvelopedData decryption. [eap-8.1.z] (CVE-2026-12802)

    * bcpg-jdk18on: Bouncy Castle for Java: Integrity compromise due to insufficient tag-length enforcement in     CMS AuthEnvelopedData decryption. [eap-8.1.z] (CVE-2026-12802)

    * bcutil-jdk18on: Bouncy Castle for Java: Integrity compromise due to insufficient tag-length enforcement     in CMS AuthEnvelopedData decryption. [eap-8.1.z] (CVE-2026-12802)

    * bcpkix-jdk18on: Bouncy Castle for Java: Integrity compromise due to insufficient tag-length enforcement     in CMS AuthEnvelopedData decryption. [eap-8.1.z] (CVE-2026-12802)

    * bcjmail-jdk18on: Bouncy Castle for Java: Denial of Service via OER parser unbounded recursion     [eap-8.1.z] (CVE-2026-59645)

    * bcpg-jdk18on: Bouncy Castle for Java: Denial of Service via OER parser unbounded recursion [eap-8.1.z]     (CVE-2026-59645)

    * bcutil-jdk18on: Bouncy Castle for Java: Denial of Service via OER parser unbounded recursion [eap-8.1.z]     (CVE-2026-59645)

    * bcpkix-jdk18on: Bouncy Castle for Java: Denial of Service via OER parser unbounded recursion [eap-8.1.z]     (CVE-2026-59645)

    * bcprov-jdk18on: Bouncy Castle for Java: Denial of Service via OER parser unbounded recursion [eap-8.1.z]     (CVE-2026-59645)

    * bcprov-jdk18on: Bouncy Castle for Java: Integrity compromise due to insufficient tag-length enforcement     in CMS AuthEnvelopedData decryption. [eap-8.1.z] (CVE-2026-12802)

    * bcjmail-jdk18on: Bouncy Castle for Java: Cryptographic signature bypass [eap-8.1.z] (CVE-2026-59639)

    * bcpg-jdk18on: Bouncy Castle for Java: Cryptographic signature bypass [eap-8.1.z] (CVE-2026-59639)

    * bcpkix-jdk18on: Bouncy Castle for Java: Cryptographic signature bypass [eap-8.1.z] (CVE-2026-59639)

    * bcprov-jdk18on: Bouncy Castle for Java: Cryptographic signature bypass [eap-8.1.z] (CVE-2026-59639)

    * bcjmail-jdk18on: Bouncy Castle for Java: Data integrity bypass due to improper cryptographic binding in     CMS AuthenticatedData [eap-8.1.z] (CVE-2026-59642)

    * bcpg-jdk18on: Bouncy Castle for Java: Data integrity bypass due to improper cryptographic binding in CMS     AuthenticatedData [eap-8.1.z] (CVE-2026-59642)

    * bcutil-jdk18on: Bouncy Castle for Java: Data integrity bypass due to improper cryptographic binding in     CMS AuthenticatedData [eap-8.1.z] (CVE-2026-59642)

    * bcpkix-jdk18on: Bouncy Castle for Java: Data integrity bypass due to improper cryptographic binding in     CMS AuthenticatedData [eap-8.1.z] (CVE-2026-59642)

    * bcprov-jdk18on: Bouncy Castle for Java: Data integrity bypass due to improper cryptographic binding in     CMS AuthenticatedData [eap-8.1.z] (CVE-2026-59642)

    * bcjmail-jdk18on: Bouncy Castle for Java: Denial of Service via unbounded HSS public-key level count     [eap-8.1.z] (CVE-2026-58060)

    * bcpg-jdk18on: Bouncy Castle for Java: Denial of Service via unbounded HSS public-key level count     [eap-8.1.z] (CVE-2026-58060)

    * bcutil-jdk18on: Bouncy Castle for Java: Denial of Service via unbounded HSS public-key level count     [eap-8.1.z] (CVE-2026-58060)

    * bcpkix-jdk18on: Bouncy Castle for Java: Denial of Service via unbounded HSS public-key level count     [eap-8.1.z] (CVE-2026-58060)

    * bcprov-jdk18on: Bouncy Castle for Java: Denial of Service via unbounded HSS public-key level count     [eap-8.1.z] (CVE-2026-58060)

    * bcpg-jdk18on: Bouncy Castle for Java: Integrity bypass in CCM-family modes [eap-8.1.z] (CVE-2026-58061)

    * bcprov-jdk18on: Bouncy Castle for Java: Integrity bypass in CCM-family modes [eap-8.1.z]     (CVE-2026-58061)

    * sshd-core: Apache MINA SSHD: Asynchronous authentication can bypass signature verification [eap-8.1.z]     (CVE-2026-77185)

    * jackson-core: jackson-core: Denial of Service via excessively long JSON property names [eap-8.1.z]     (CVE-2026-68498)

    * bcutil-jdk18on: Bouncy Castle: Certificate validation bypass via missing name constraint checks     [eap-8.1.z] (CVE-2026-71889)

    * bcjmail-jdk18on: Bouncy Castle: Certificate validation bypass via missing name constraint checks     [eap-8.1.z] (CVE-2026-71889)

    * bcpg-jdk18on: Bouncy Castle: Certificate validation bypass via missing name constraint checks     [eap-8.1.z] (CVE-2026-71889)

    * bcprov-jdk18on: Bouncy Castle: Certificate validation bypass via missing name constraint checks     [eap-8.1.z] (CVE-2026-71889)

    * bcpkix-jdk18on: Bouncy Castle: Certificate validation bypass via missing name constraint checks     [eap-8.1.z] (CVE-2026-71889)

    * jackson-core: Jackson-core: Denial of Service via unbounded StringBuilder growth during malformed token     processing [eap-8.1.z] (CVE-2026-89425)

    * jackson-databind: Jackson-databind: Denial of Service via quadratic forward-reference completion     [eap-8.1.z] (CVE-2026-91777)

    * bcpg-jdk18on: Bouncy Castle: Signature misattribution via missing subkey cross-certification validation     [eap-8.1.z] (CVE-2026-71887)

    * sshd-core: Apache MINA SSHD: Authentication bypass via duplicate public key presentation [eap-8.1.z]     (CVE-2026-93994)

    * xmlschema-core: Apache XMLSchema: Denial of Service (DoS) via deeply nested schema structures     [eap-8.1.z] (CVE-2026-102496)

    * xmlschema-core: Apache XMLSchema: Denial of Service via unbounded recursion during schema parsing     [eap-8.1.z] (CVE-2026-102495)

    * jackson-core: Jackson-core: Denial of Service via regular expression backtracking [eap-8.1.z]     (CVE-2026-89407)

    * neethi: Neethi: Denial of Service via crafted WS-Policy documents [eap-8.1.z] (CVE-2026-91866)

    * neethi: Apache Neethi: Denial of Service via crafted WS-Policy documents [eap-8.1.z] (CVE-2026-91865)

    * neethi: Apache Neethi: Denial of Service via uncontrolled recursion in WS-Policy document parsing     [eap-8.1.z] (CVE-2026-91863)

    * neethi: Apache Neethi: Denial of Service via crafted WS-Policy documents [eap-8.1.z] (CVE-2026-91864)

    * wildfly-server: wildfly: RBAC bypass in WildFly deployment-operation handlers leads to privilege     escalation [eap-8.1.z] (CVE-2026-12977)

    For more details about the security issue(s), including the impact, a CVSS     score, acknowledgments, and other related information, refer to the CVE page(s)     listed in the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux 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 SUSE Linux SLED15 / SLED_SAP15 / SLES15 / SLES_SAP15 host has a package installed that is affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:4622-1 advisory.

    - CVE-2026-77185: Asynchronous authentication can bypass signature verification (bsc#1283357).
    - CVE-2026-93994: Repeated-publickey policy bypass on server (bsc#1283352).
    - CVE-2026-93995: Remote execution of JGit 'archive -o=file.zip' can write file on the server     (bsc#1283350).
    - CVE-2026-93996: Memory exhaustion DoS via unbounded SCP command line read (bsc#1283348).
    - CVE-2026-94002: Memory exhaustion in SFTP client via unsolicited SFTP replies (bsc#1283347).
    - CVE-2026-94029: Memory exhaustion in SFTP v6 check-file-name/check-file-handle extension (bsc#1283346).
    - CVE-2026-94052: LDAP password authentication ineffective (bsc#1283345).
    - CVE-2026-94053: LDAP injection in sshd-ldap (bsc#1283344).

    Changes for apache-sshd:

    - Update to upstream version 2.20.0:
     + GH-656 ChannelPipedInputStream: shrink buffer when emptied      + GH-906 Fix finding a signature factory for BC ed25519 keys      + GH-911 Fix server-side SOCKS5 proxy for fragmented and      pipelined CONNECT requests      + Allow asynchronous authentication only for password and      keyboard-interactive authentication schemes      + Fix authentication requiring multiple public keys      (server-side)      + Better argument handling in sshd-git      + More checks in authentication (server-side)      + Better SCP command handling      + SFTP client: simplify response message handling      + Fix check-file-name/check-file-handle SFTP v6 extension      + Improve LDAP authentication (sshd-ldap)
     * New Features      + GH-905 Implement the 'from' and 'expiry-time' options in      authorized_keys handling in public key authentication (server      side)

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.

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

  - Authentication bypass in sshd-core in Apache MINA SSHD versions 2.0.0 to 2.19.0 and 3.0.0-M1 to 3.0.0-M5     for a certain (presumed rare) way to implement an SSH server. Apache MINA SSHD is a Java library for     client- and server-side SSH. In the server part of the library, a mechanism to perform asynchronous     authentication exists. A server implemented with Apache MINA SSHD must contain explicit code to make use     of this feature. The implementation of this feature was flawed and could potentially lead to skipping     checking the signature in public-key or hostbased authentication, or returning a wrong result. Users are     recommended to upgrade to Apache MINA SSHD 2.20.0 or 3.0.0-M6, which fix the logic error and which     additionally forbid the use of this asynchronous authentication mechanism with the public-key or     hostbased authentication schemes: if used, the SSH session will be closed and the server will log an entry     indicating that asynchronous authentication may be used only with password or keyboard-interactive     authentication. (CVE-2026-77185)

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

ID	Name	Product	Family	Type	Severity
379078	RHEL 10 / 8 / 9 : Red Hat JBoss Enterprise Application Platform 8.1.9 (RHSA-2026:99018)	Nessus	Red Hat Local Security Checks	Local	high
365326	SUSE SLED15 / SLES15 Security Update : apache-sshd (SUSE-SU-2026:4622-1)	Nessus	SuSE Local Security Checks	Local	critical
351264	Linux Distros Unpatched Vulnerability : CVE-2026-77185	Nessus	Misc.	Local	critical

Detections

Analytics

CVE-2026-77185

critical

Tenable Plugins

high

critical

critical