SuperTokens Core: SAML XML Signature Wrapping authentication bypass — any IdP user can authenticate as any other user
Affects SuperTokens Core 11.3.0–11.3.6, 11.4.0–11.4.6, and 12.0.6–12.0.9 with a licensed SAML feature and at least one SAML client. Fixed in 11.3.7, 11.4.7, and 12.0.10.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Exploited
- No known exploitation
- Fix
- Fixed in 12.0.10, 11.4.7, 11.3.7
- Who is exposed
- Specific setups only
Do first: Check whether your setup matches what the bug needs. SAML enterprise feature must be licensed and at least one SAML client configured
- Last modified
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 16/100 · provisional
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Specific setups only
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
SuperTokens Core, an open source authentication server, has an authentication bypass in its SAML login handling that lets a user of the configured identity provider sign in as another user. Remotely, with low privileges and no user interaction, an attacker can exploit it to impersonate other identity provider users and gain access to their accounts.
Read the original description
SuperTokens Core is an open source authentication server. From 11.3.0 until 11.3.7, 11.4.7, and 12.0.10, SAML.verifySamlResponseSignature calls OpenSAML SignatureValidator.validate without first applying SAMLSignatureProfileValidator. The Core can therefore accept a cryptographically valid signature that references a different XML element from the Response or Assertion whose NameID and attributes are used for authentication. An ordinary user of the configured identity provider can move a genuinely signed element elsewhere in the document while supplying an attacker-authored identity-bearing element, causing XML Signature Wrapping authentication as another IdP user. Both response-level and assertion-level signing paths are affected, and SP-initiated login remains reachable without enabling allowIDPInitiatedLogin. This issue is fixed in versions 11.3.7, 11.4.7, and 12.0.10.
cve.now Index
- Exploitation?/40Unknown. No CISA SSVC exploitation rating yet
- Exposure8/25Specific setups only, reachable over the network
- Reach?/20Unknown. No tracked technology or package matched
- Severity8.1/10CVSS 8.1
- No patch0/5No signal
What would change the score
- Would score about 66 if added to CISA KEV
- Would score about 61 if CISA's SSVC rates exploitation active
- Would score about 23 if CISA's SSVC rates it automatable
What to do
Check whether your setup matches what the bug needs.
SAML enterprise feature must be licensed and at least one SAML client configuredUpgrade to a fixed version: 12.0.10, 11.4.7, 11.3.7.
Timeline
- CVE published
- First seen by cve.now
Affected versions
- supertokens supertokens-core
From 12.0.6 · fixed in 12.0.10; From 11.4.0 · fixed in 11.4.7; From 11.3.0 · fixed in 11.3.7
Evidence 7
- Advisory
- Repository
- Repository
- Repository
- Repository
Show all 7 sourcesShow fewer sources
- Repository
- Repository
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-123798
Is CVE-2026-123798 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
What does this mean?
The flaw is an XML signature wrapping issue in SAML login. It lets an ordinary user of the configured identity provider (IdP) authenticate as another user of that same IdP.Source: github.com
Which versions are affected by CVE-2026-123798?
supertokens-core: from 12.0.6 before 12.0.10; from 11.4.0 before 11.4.7; from 11.3.0 before 11.3.7.Source: cve.now feed data
Am I affected, and how do I check?
Versions 11.3.0 up to 11.3.7, 11.4.0 up to 11.4.7, and 12.0.6 up to 12.0.10 are in the affected ranges, with fixes in 11.3.7, 11.4.7, and 12.0.10. The bug only applies when the enterprise SAML feature is licensed and at least one SAML client is configured, so check the installed Core version and those two settings.Source: github.com
How do I fix CVE-2026-123798?
Upgrade to the fixed release on your branch: 12.0.10, 11.4.7, or 11.3.7.Source: github.com