CVE-2026-89043 is a high severity saml signature wrapping flaw in passport-saml-encrypted, scored 7.4. The record names no fixed version. Check your installed version against the affected list below, then patch or restrict access until you can. The record does not flag it as exploited.
What's affected
- passport-saml-encrypted through 0.1.13.
Severity in the record: High (7.4), vector CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N. Weakness: CWE-347.
Fix: The record names no fixed version. Check the project issue 30 and consider moving to a maintained SAML library.
How to check if you're exposed
- Run
npm ls passport-saml-encryptedin each project. - For lockfiles:
grep -n passport-saml-encrypted package-lock.json.
Run these on every host, image and build that could carry the component. Dependency files in repositories and base images in registries are easy to miss.
What to do now
- Confirm the version of every affected system using the checks above.
- Read the vendor advisory linked in Sources and note the fixed version for your release line.
- Schedule the update, starting with systems that face untrusted networks or hold the most sensitive data.
- In the meantime: check whether the package is still maintained for your use and plan a replacement.
- Record the change, then recheck the version to confirm it took effect.
Why it matters
Signature verification and assertion extraction use separate XPath lookups with no cross-check. Someone holding any validly signed SAML message can prepend a forged, unsigned assertion; it is accepted as the identity while the real signature validates against the original. This is CWE-347, improper verification of a cryptographic signature. The impact is identity forgery in single sign-on, rated 7.4 with high attack complexity.
The record's KEV flag is false, so this post makes no claim that the flaw is exploited in the wild. That can change, so recheck the CISA catalog from time to time.
Libraries like this often arrive as transitive dependencies, so the version in your lockfile may not be one you chose. Safeguard's free in-browser dependency scan can show whether the package is in a project, and reachability analysis helps separate code paths that call the weak function from those that never do.
Try it yourself
Click through it at your own pace, or open it full screen.
The vector string in the record is a compact summary of how the flaw is reached and what it costs. AV is the attack vector (network, adjacent or local), PR is the privilege the attacker needs, and the C, I and A letters give the impact on confidentiality, integrity and availability. Read it against your own network layout rather than relying on the score alone.
After you patch
Patching is not the end of the job. Recheck the version on each system, because an upgrade that failed or rolled back looks the same as a success until someone looks. Keep the advisory link with your change record so the next reviewer can see why the update happened.
If you cannot patch soon, write down the reason, the compensating control you chose and a date to revisit. Exceptions without a date tend to become permanent.
Quick check
Does an attacker need a valid login?
They need a validly signed SAML message from your identity provider, per the record.
Sources
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GitHub: project repository
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Safeguard Gold: CVE-2026-89043
Last reviewed: 18 October 2026.
