Start with Identity
Protocol · 22 briefs · 3 on CISA KEV

SAML identity CVEs

Signature wrapping and parser differentials keep turning one valid assertion into a login as any user. If you run workforce SSO on SAML, this is the protocol page to start with.

How this protocol fails

SAML is still how a large share of enterprise SSO works. The 2024-2026 failures are almost all the same bug in different clothes: the verifier checks a signature on one XML tree and consumes NameID or attributes from another. ruby-saml, samlify, GitHub Enterprise Server, Keycloak, FortiCloud SSO, and HaloITSM all failed that test. A single leaked or captured signature is enough. Encrypted assertions did not save GHES. Incomplete fixes came back as new CVEs within months. On a firewall or VPN ACS, the same class is actively exploited and on CISA KEV.

What security people should do

  • Inventory every ACS that verifies SAML itself, not only the IdP. GitLab, GHES, homegrown Rails and Node SPs, and appliance SSO all count.
  • Upgrade SAML libraries past the incomplete-fix lines (ruby-saml 1.18.1 or later, samlify 2.10.0 or later) and rotate IdP signing keys after you patch.
  • Prefer a single XML stack. Dual parsers (ReXML plus Nokogiri) are how wrapping survives a "we patched" ticket.
  • Disable FortiCloud SSO and similar appliance SAML if you do not need it. Hunt for rogue admins after any KEV SAML bypass.
  • Add a regression test: a known wrapping fixture must fail after every library bump.

CVEs in this category

22
SAML
3
On CISA KEV
3
Actively exploited
22
Showing
Severity
Year
Status

Showing 22 of 22

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