The X509_V_FLAG_X509_STRICT flag enables additional security checks of the certificates present in a certificate chain. It is not set by default. Starting from OpenSSL version 1.1.1h a check to disallow certificates in the chain that have explicitly encoded elliptic curve parameters was added as an additional strict check. An error in the implementation of this check meant that the result of a previous check to confirm that certificates in the chain are valid CA certificates was overwritten. This effectively bypasses the check that non-CA certificates must not be able to issue other certificates. If a "purpose" has been configured then there is a subsequent opportunity for checks that the certificate is a valid CA. All of the named "purpose" values implemented in libcrypto perform this check. Therefore, where a purpose is set the certificate chain will still be rejected even when the strict flag has been used. A purpose is set by default in libssl client and server certificate verification routines, but it can be overridden or removed by an application. In order to be affected, an application must explicitly set the X509_V_FLAG_X509_STRICT verification flag and either not set a purpose for the certificate verification or, in the case of TLS client or server applications, override the default purpose. OpenSSL versions 1.1.1h and newer are affected by this issue. Users of these versions should upgrade to OpenSSL 1.1.1k. OpenSSL 1.0.2 is not impacted by this issue. Fixed in OpenSSL 1.1.1k (Affected 1.1.1h-1.1.1j).

Nessus versions 8.11.0 and earlier were found to maintain sessions longer than the permitted period in certain scenarios. The lack of proper session expiration could allow attackers with local access to login into an existing browser session.

Nessus 8.10.0 and earlier were found to contain a Stored XSS vulnerability due to improper validation of input during scan configuration. An authenticated, remote attacker could potentially exploit this vulnerability to execute arbitrary code in a user's session. Tenable has implemented additional input validation mechanisms to correct this issue in Nessus 8.11.0.

Tenable Nessus before 6.8 has a stored XSS issue that requires admin-level authentication to the Nessus UI, and would potentially impact other admins (Tenable IDs 5218 and 5269).

Tenable Nessus before 6.8 has a stored XSS issue that requires admin-level authentication to the Nessus UI, and would only potentially impact other admins. (Tenable ID 5198).

Nessus versions 8.6.0 and earlier were found to contain a Denial of Service vulnerability due to improper validation of specific imported scan types. An authenticated, remote attacker could potentially exploit this vulnerability to cause a Nessus scanner to become temporarily unresponsive.

Nessus 8.5.2 and earlier on Windows platforms were found to contain an issue where certain system files could be overwritten arbitrarily, potentially creating a denial of service condition.

Content Injection vulnerability in Tenable Nessus prior to 8.5.0 may allow an authenticated, local attacker to exploit this vulnerability by convincing another targeted Nessus user to view a malicious URL and use Nessus to send fraudulent messages. Successful exploitation could allow the authenticated adversary to inject arbitrary text into the feed status, which will remain saved post session expiration.

Nessus versions 8.4.0 and earlier were found to contain a reflected XSS vulnerability due to improper validation of user-supplied input. An unauthenticated, remote attacker could potentially exploit this vulnerability via a specially crafted request to execute arbitrary script code in a users browser session.

If an application encounters a fatal protocol error and then calls SSL_shutdown() twice (once to send a close_notify, and once to receive one) then OpenSSL can respond differently to the calling application if a 0 byte record is received with invalid padding compared to if a 0 byte record is received with an invalid MAC. If the application then behaves differently based on that in a way that is detectable to the remote peer, then this amounts to a padding oracle that could be used to decrypt data. In order for this to be exploitable "non-stitched" ciphersuites must be in use. Stitched ciphersuites are optimised implementations of certain commonly used ciphersuites. Also the application must call SSL_shutdown() twice even if a protocol error has occurred (applications should not do this but some do anyway). Fixed in OpenSSL 1.0.2r (Affected 1.0.2-1.0.2q).

Nessus versions 8.2.1 and earlier were found to contain a stored XSS vulnerability due to improper validation of user-supplied input. An authenticated, remote attacker could potentially exploit this vulnerability via a specially crafted request to execute arbitrary script code in a user's browser session. Tenable has released Nessus 8.2.2 to address this issue.

Simultaneous Multi-threading (SMT) in processors can enable local users to exploit software vulnerable to timing attacks via a side-channel timing attack on 'port contention'.

In Nessus before 7.1.0, Session Fixation exists due to insufficient session management within the application. An authenticated attacker could maintain system access due to session fixation after a user password change.

In Nessus before 7.1.0, a XSS vulnerability exists due to improper input validation. A remote authenticated attacker could create and upload a .nessus file, which may be viewed by an administrator allowing for the execution of arbitrary script code in a user's browser session. In other scenarios, XSS could also occur by altering variables from the Advanced Settings.

When installing Nessus to a directory outside of the default location, Nessus versions prior to 7.0.3 did not enforce secure permissions for sub-directories. This could allow for local privilege escalation if users had not secured the directories in the installation location.

The moment module before 2.19.3 for Node.js is prone to a regular expression denial of service via a crafted date string, a different vulnerability than CVE-2016-4055.

Tenable Nessus before 6.10.2 (as used alone or in Tenable Appliance before 4.5.0) was found to contain a flaw that allowed a remote, authenticated attacker to upload a crafted file that could be written to anywhere on the system. This could be used to subsequently gain elevated privileges on the system (e.g., after a reboot). This issue only affects installations on Windows.

Cross-site scripting (XSS) vulnerability in Tenable Nessus before 6.9 allows remote authenticated users to inject arbitrary web script or HTML via vectors related to handling of .nessus files.

The duration function in the moment package before 2.11.2 for Node.js allows remote attackers to cause a denial of service (CPU consumption) via a long string, aka a "regular expression Denial of Service (ReDoS)."

Cross-site scripting (XSS) vulnerability in Tenable Nessus before 6.9.3 allows remote authenticated users to inject arbitrary web script or HTML via unspecified vectors.