Loading vulnerability…
CVE-2026-2673 is a low-severity flaw in OpenSSL TLS 1.3 server-side key agreement group selection affecting OpenSSL 3.5 and 3.6. The issue occurs when the server’s configured key exchange group list uses the DEFAULT keyword to interpolate the built-in default group list while also relying on the newer tuple-based group selection semantics introduced in OpenSSL 3.5. Due to an implementation defect, the interpolated default list loses its tuple structure during configuration processing, causing all configured server-supported groups to be treated as a single sufficiently secure tuple. As a result, when a client supports a more preferred mutually supported group but does not include a corresponding initial keyshare, the server may fail to send the expected Hello Retry Request and instead negotiate a less preferred group from the client’s predicted keyshares. This can silently defeat intended preference ordering, including for hybrid post-quantum groups, and cause the connection to complete with a weaker-than-intended key agreement choice. OpenSSL stated that the affected code is outside the FIPS boundary and that OpenSSL FIPS modules are not impacted.
Mallory correlates every CVE against your assets, your vendors, and active adversary campaigns. Know which vulnerabilities matter for you, not just which ones are loud.
What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.
What an attacker gets, and what they’ve been doing with it.
If you can’t patch tonight, do this now.
Patch, then assume compromise.
No public exploits tracked yet. Mallory keeps watching.
No public exploit code observed for this vulnerability.
Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.
Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.
33 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
Loss of key agreement group tuple structure when the DEFAULT keyword is used in server-side configuration of the key-agreement group list in OpenSSL.
A configuration validation flaw where using the DEFAULT keyword in server-side key-agreement group configuration can silently degrade negotiated key groups by losing tuple structure.
A low-severity OpenSSL TLS 1.3 vulnerability where servers using the "DEFAULT" keyword in key exchange group configuration may select a less preferred mutually supported key agreement group and fail to trigger Hello Retry Request behavior as intended, potentially preventing negotiation of preferred post-quantum groups.
Query your assets running an affected version, and investigate the blast radius.
Every observed campaign linking this CVE to a named adversary.
Malware families riding this exploit, with evidence and IOCs.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.