It is, therefore, affected by a vulnerability as referenced in the ALAS2023-2026-1522 advisory.

    Issue summary: An OpenSSL TLS 1.3 server may fail to negotiate the expected preferred key exchange group     when its key exchange group configuration includes the default by using the 'DEFAULT' keyword. Impact     summary: A less preferred key exchange may be used even when a more preferred group is supported by both     client and server, if the group was not included among the client's initial predicated keyshares. This     will sometimes be the case with the new hybrid post-quantum groups, if the client chooses to defer their     use until specifically requested by the server. If an OpenSSL TLS 1.3 server's configuration uses the     'DEFAULT' keyword to interpolate the built-in default group list into its own configuration, perhaps     adding or removing specific elements, then an implementation defect causes the 'DEFAULT' list to lose its     'tuple' structure, and all server-supported groups were treated as a single sufficiently secure 'tuple',     with the server not sending a Hello Retry Request (HRR) even when a group in a more preferred tuple was     mutually supported. As a result, the client and server might fail to negotiate a mutually supported post-     quantum key agreement group, such as 'X25519MLKEM768', if the client's configuration results in only     'classical' groups (such as 'X25519' being the only ones in the client's initial keyshare prediction).
    OpenSSL 3.5 and later support a new syntax for selecting the most preferred TLS 1.3 key agreement group on     TLS servers. The old syntax had a single 'flat' list of groups, and treated all the supported groups as     sufficiently secure. If any of the keyshares predicted by the client were supported by the server the most     preferred among these was selected, even if other groups supported by the client, but not included in the     list of predicted keyshares would have been more preferred, if included. The new syntax partitions the     groups into distinct 'tuples' of roughly equivalent security. Within each tuple the most preferred group     included among the client's predicted keyshares is chosen, but if the client supports a group from a more     preferred tuple, but did not predict any corresponding keyshares, the server will ask the client to retry     the ClientHello (by issuing a Hello Retry Request or HRR) with the most preferred mutually supported     group. The above works as expected when the server's configuration uses the built-in default group list,     or explicitly defines its own list by directly defining the various desired groups and group 'tuples'. No     OpenSSL FIPS modules are affected by this issue, the code in question lies outside the FIPS boundary.
    OpenSSL 3.6 and 3.5 are vulnerable to this issue. OpenSSL 3.6 users should upgrade to OpenSSL 3.6.2 once     it is released. OpenSSL 3.5 users should upgrade to OpenSSL 3.5.6 once it is released. OpenSSL 3.4, 3.3,     3.0, 1.0.2 and 1.1.1 are not affected by this issue. (CVE-2026-2673)

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.

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Amazon Linux 2023 : openssl, openssl-devel, openssl-fips-provider-latest (ALAS2023-2026-1522)

medium Nessus Plugin ID 304598

Version 1.3

Version 1.2

Version 1.1

Version 1.3 May 20, 2026, 3:58 PM CVSS metrics ("CVSSv3 score" set to 6.5) CVSS metrics ("CVSSv3 vector" set to "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L") CVSSv3 severity (based on None, severity decreased from "High" to "Medium") Plugin Feed: 202605201558
Version 1.2 Apr 10, 2026, 7:42 PM Plugin metadata (Add IAVM Info) Plugin Feed: 202604101942
Version 1.1 Apr 2, 2026, 9:07 AM New Plugin Feed: 202604020907