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

  - Issue summary: Calling the OpenSSL API function SSL_select_next_proto with an empty supported client     protocols buffer may cause a crash or memory contents to be sent to the peer. Impact summary: A buffer     overread can have a range of potential consequences such as unexpected application beahviour or a crash.
    In particular this issue could result in up to 255 bytes of arbitrary private data from memory being sent     to the peer leading to a loss of confidentiality. However, only applications that directly call the     SSL_select_next_proto function with a 0 length list of supported client protocols are affected by this     issue. This would normally never be a valid scenario and is typically not under attacker control but may     occur by accident in the case of a configuration or programming error in the calling application. The     OpenSSL API function SSL_select_next_proto is typically used by TLS applications that support ALPN     (Application Layer Protocol Negotiation) or NPN (Next Protocol Negotiation). NPN is older, was never     standardised and is deprecated in favour of ALPN. We believe that ALPN is significantly more widely     deployed than NPN. The SSL_select_next_proto function accepts a list of protocols from the server and a     list of protocols from the client and returns the first protocol that appears in the server list that also     appears in the client list. In the case of no overlap between the two lists it returns the first item in     the client list. In either case it will signal whether an overlap between the two lists was found. In the     case where SSL_select_next_proto is called with a zero length client list it fails to notice this     condition and returns the memory immediately following the client list pointer (and reports that there was     no overlap in the lists). This function is typically called from a server side application callback for     ALPN or a client side application callback for NPN. In the case of ALPN the list of protocols supplied by     the client is guaranteed by libssl to never be zero in length. The list of server protocols comes from the     application and should never normally be expected to be of zero length. In this case if the     SSL_select_next_proto function has been called as expected (with the list supplied by the client passed in     the client/client_len parameters), then the application will not be vulnerable to this issue. If the     application has accidentally been configured with a zero length server list, and has accidentally passed     that zero length server list in the client/client_len parameters, and has additionally failed to correctly     handle a no overlap response (which would normally result in a handshake failure in ALPN) then it will     be vulnerable to this problem. In the case of NPN, the protocol permits the client to opportunistically     select a protocol when there is no overlap. OpenSSL returns the first client protocol in the no overlap     case in support of this. The list of client protocols comes from the application and should never normally     be expected to be of zero length. However if the SSL_select_next_proto function is accidentally called     with a client_len of 0 then an invalid memory pointer will be returned instead. If the application uses     this output as the opportunistic protocol then the loss of confidentiality will occur. This issue has been     assessed as Low severity because applications are most likely to be vulnerable if they are using NPN     instead of ALPN - but NPN is not widely used. It also requires an application configuration or programming     error. Finally, this issue would not typically be under attacker control making active exploitation     unlikely. The FIPS modules in 3.3, 3.2, 3.1 and 3.0 are not affected by this issue. Due to the low     severity of this issue we are not issuing new releases of OpenSSL at this time. The fix will be included     in the next releases when they become available. (CVE-2024-5535)

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Linux Distros Unpatched Vulnerability : CVE-2024-5535

critical Nessus Plugin ID 248840

Version 1.7

Version 1.6

Version 1.5

Version 1.7 Dec 2, 2025, 7:12 AM Detection (updated detection logic) Plugin metadata Plugin Feed: 202512020712
Version 1.6 Nov 21, 2025, 2:12 PM Detection (updated detection logic) Plugin metadata Plugin Feed: 202511211412
Version 1.5 Nov 7, 2025, 11:55 PM CVSS temporal metrics ("CVSSv2 temporal vector" set to "CVSS2#E:POC/RL:U/RC:C") CVSS temporal metrics ("CVSSv3 temporal vector" set to "CVSS:3.0/E:P/RL:U/RC:C") Detection (updated detection logic) Plugin metadata Plugin Feed: 202511072355