Evidence used
- No CISA KEV confirmation is currently recorded.
- The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
- EPSS is 0.28% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2026
CVE-2026-96760High confidence
Authlib library contains a signature‑verification bypass vulnerability
Authlib · Authlib
9.8CriticalCVSS 3.1
Patch only the product branches with a verified fix
Fix availability varies by productCritical technical impact with a remotely reachable, unauthenticated path; no CISA KEV confirmation is currently recorded. Verified remediation exists for at least one product or source, but 24 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityCritical→Operational priority:Critical, unchanged from published severity.unchanged
Compensating controls
- Apply the linked authoritative mitigation while planning the permanent fix.
- Restrict the affected network interface to trusted sources where business-safe.
- Monitor vendor guidance and exploitation sources for a material change.
Verification
- Confirm that the asset runs Authlib Authlib and falls inside the recorded affected range.
- Recheck the vendor advisory before scheduling a change because no verified fixed version is currently retained.
- Validate exposure, authentication requirements and compensating controls in the actual environment.
- Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Remediation availability differs by product scope
Verified remediation exists for at least one product or source, but 24 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.
- Red Hat Product Security: 10 affected or under-investigation product states without a fixed product state in the same current advisory
- SUSE Product Security Team: 14 affected or under-investigation product states without a fixed product state in the same current advisory
Distribution package intelligence
1 package stateRelease-specific package status
ubuntu findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.
Repository candidate not checked
A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.
| Distribution release | Source package | Vendor state | Fixed version | Evidence |
|---|---|---|---|---|
| Ubuntu 24.04 LTSnoble · esm-apps | python-authlib | Under evaluationCanonical reports that the package might be affected and still needs evaluation or fixing. | Not published in this feed | Canonical Ubuntu Security ↗Source updated 2 Oct 2026 |
Direct vendor intelligence
2 currentAuthoritative vendor CSAF and VEX advisories
Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.
CVE-2026-96760 · CSAF 2.0 · revision 3 · finalRed Hat Product Securityauthlib: authlib: Signature verification bypass via deserialize_json
The vendor explicitly identifies these products as affected by this CVE.
- exploit-intelligence/vulnerability-analysis-rhel9 as a component of Exploit Intelligence
- lightspeed-core/lightspeed-stack-rhel9 as a component of Lightspeed Core
- mta/mta-solution-server-rhel9 as a component of Migration Toolkit for Applications 8
- openshift-lightspeed/lightspeed-agentic-sandbox-rhel9 as a component of OpenShift Lightspeed
- ansible-automation-platform-26/lightspeed-chatbot-rhel9 as a component of Red Hat Ansible Automation Platform 2
- ansible-automation-platform-27/lightspeed-chatbot-rhel9 as a component of Red Hat Ansible Automation Platform 2
- rhel-cla/rhel-knowledge-bridge-rhel10 as a component of Red Hat Enterprise Linux command line assistant
- container-native-virtualization/ocp-virt-validation-checkup-rhel9 as a component of Red Hat OpenShift Virtualization 4
- openshift-virtualization/ocp-virt-validation-checkup-rhel9 as a component of Red Hat OpenShift Virtualization 4
- satellite/foreman-mcp-server-rhel9 as a component of Red Hat Satellite 6
- Summary
- A flaw was found in authlib. This flaw allows a remote attacker to bypass digital signature verification and submit forged data. When processing a JSON Web Signature (JWS, a format used to verify data integrity), the deserialize_json() function marks payloads as successfully verified without validating cryptographic signatures or requiring a verification key. Consequently, an attacker can supply manipulated data that the application treats as authentic and trusted, potentially leading to unauthorized access.
- Remediation
- Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
CVE-2026-96760 · CSAF 2.0 · revision 2 · interimSUSE Product Security TeamCVE-2026-96760
The vendor explicitly identifies these products as affected by this CVE.
- python-Authlib as component of SUSE Linux Enterprise Desktop 15 SP7
- python311-Authlib as component of SUSE Linux Enterprise Desktop 15 SP7
- python-Authlib as component of SUSE Linux Enterprise Module for Python 3 15 SP7
- python311-Authlib as component of SUSE Linux Enterprise Module for Python 3 15 SP7
- python-Authlib as component of SUSE Linux Enterprise Server 15 SP6-LTSS
- python311-Authlib as component of SUSE Linux Enterprise Server 15 SP6-LTSS
- python-Authlib as component of SUSE Linux Enterprise Server 15 SP6
- python311-Authlib as component of SUSE Linux Enterprise Server 15 SP6
- python-Authlib as component of SUSE Linux Enterprise Server 15 SP7
- python311-Authlib as component of SUSE Linux Enterprise Server 15 SP7
- python-Authlib as component of SUSE Linux Enterprise Server for SAP Applications 15 SP6
- python311-Authlib as component of SUSE Linux Enterprise Server for SAP Applications 15 SP6
- Summary
- Authlib (v1.7.2 and below) contains a signature verification bypass vulnerability. The JsonWebSignature.deserialize_json() method accepts a JSON Serialization JWS object and returns the payload as successfully verified without checking for a signature and without requiring a cryptographic key.
- Remediation
- No remediation text is recorded.
Critical technical impact with a remotely reachable, unauthenticated path; no CISA KEV confirmation is currently recorded. Verified remediation exists for at least one product or source, but 24 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.
Fix availability varies by product01
What, why and how
Authlib (v1.7.2 and below) contains a signature verification bypass vulnerability. The JsonWebSignature.deserialize_json() method accepts a JSON Serialization JWS object and returns the payload as successfully verified without checking for a signature and without requiring a cryptographic key.
What
Authlib (v1.7.2 and below) contains a signature verification bypass vulnerability. The JsonWebSignature.deserialize_json() method accepts a JSON Serialization JWS object and returns the payload as successfully verified without checking for a signature and without requiring a cryptographic key.
Why
The product does not verify, or incorrectly verifies, the cryptographic signature for data.
How
An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
What
Authlib (v1.7.2 and below) contains a signature verification bypass vulnerability. The JsonWebSignature.deserialize_json() method accepts a JSON Serialization JWS object and returns the payload as successfully verified without checking for a signature and without requiring a cryptographic key.
Why
The product does not verify, or incorrectly verifies, the cryptographic signature for data.
How
An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
02
Exploit reality and attack path
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
Observed exploitation No confirmed evidence
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
Public PoC / exploit material None recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
- Likely attack path
- a network path → Improper Verification of Cryptographic Signature → cause the confidentiality, integrity or availability impact described by the vendor
- Attack surface
- Network
- Privileges required
- None: unauthenticated exploitation is possible
- User interaction
- None
- Attack complexity
- Low: no specialised conditions are recorded
- Security boundary
- Unchanged: impact remains within the vulnerable component's security authority
- Weakness
?
CWE means Common Weakness Enumeration: a standard category for the underlying weakness. - CWE-347 ↗
CWE-347: Improper Verification of Cryptographic Signature. The product does not verify, or incorrectly verifies, the cryptographic signature for data.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HCommon Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.- Post-exploitation / living off the land
- No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
03
Patch and workaround
Operational remediation based on structured source evidence.
- Status
?
Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change. - Fix availability varies by product
- Affected
- exploit-intelligence/vulnerability-analysis-rhel9 as a component of Exploit Intelligence
- lightspeed-core/lightspeed-stack-rhel9 as a component of Lightspeed Core
- mta/mta-solution-server-rhel9 as a component of Migration Toolkit for Applications 8
- openshift-lightspeed/lightspeed-agentic-sandbox-rhel9 as a component of OpenShift Lightspeed
- ansible-automation-platform-26/lightspeed-chatbot-rhel9 as a component of Red Hat Ansible Automation Platform 2
- ansible-automation-platform-27/lightspeed-chatbot-rhel9 as a component of Red Hat Ansible Automation Platform 2
- rhel-cla/rhel-knowledge-bridge-rhel10 as a component of Red Hat Enterprise Linux command line assistant
- container-native-virtualization/ocp-virt-validation-checkup-rhel9 as a component of Red Hat OpenShift Virtualization 4
- openshift-virtualization/ocp-virt-validation-checkup-rhel9 as a component of Red Hat OpenShift Virtualization 4
- satellite/foreman-mcp-server-rhel9 as a component of Red Hat Satellite 6
- Action
- Use the product-specific evidence above. Patch only products with a verified fixed release, and keep every affected or under-investigation state without a matching fix in the remediation queue.
- Workaround
- Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
04
Evidence and provenance
Published 28 Sept 2026 · Last source change 1 Oct 2026, 13:58 UTC · CWE-347 · Improper Verification of Cryptographic Signature
CVE recordCVE.org · 5.2
CVSS sourceCISA ADP
EPSS source FIRST · tracked since 2026-09-29
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2026-88465
Product sourceVendor CSAF · Red Hat Product Security
Remediation sourceVendor CSAF · Red Hat Product Security
CWE sourceCNA
NVD statusNVD awaiting enrichment
Core structured fields are present and their contributing authorities are shown above.
Material change intelligence
View recent updates ↗What changed after publication
- Affected versionsThe structured affected or fixed version information changed.Red Hat Product Security ↗
- Before
- exploit-intelligence/vulnerability-analysis-rhel9 as a component of Exploit Intelligence; lightspeed-core/lightspeed-stack-rhel9 as a component of Lightspeed Core; mta/mta-solution-server-rhel9 as a component of Migration Toolkit for Applications 8; openshift-lightspeed/lightspeed-agentic-sandbox-rhel9 as a component of OpenShift Lightspeed; ansible-automation-platform-26/lightspeed-chatbot-rhel9 as a component of Red Hat Ansible Automation Platform 2; ansible-automation-platform-27/lightspeed-chatbot-rhel9 as a component of Red Hat Ansible Automation Platform 2; rhel-cla/rhel-knowledge-bridge-rhel10 as a component of Red Hat Enterprise Linux command line assistant; container-native-virtualization/ocp-virt-validation-checkup-rhel9 as a component of Red Hat OpenShift Virtualization 4; quay/quay-rhel8 as a component of Red Hat Quay 3; quay/quay-rhel9 as a component of Red Hat Quay 3; satellite/foreman-mcp-server-rhel9 as a component of Red Hat Satellite 6
- After
- exploit-intelligence/vulnerability-analysis-rhel9 as a component of Exploit Intelligence; lightspeed-core/lightspeed-stack-rhel9 as a component of Lightspeed Core; mta/mta-solution-server-rhel9 as a component of Migration Toolkit for Applications 8; openshift-lightspeed/lightspeed-agentic-sandbox-rhel9 as a component of OpenShift Lightspeed; ansible-automation-platform-26/lightspeed-chatbot-rhel9 as a component of Red Hat Ansible Automation Platform 2; ansible-automation-platform-27/lightspeed-chatbot-rhel9 as a component of Red Hat Ansible Automation Platform 2; rhel-cla/rhel-knowledge-bridge-rhel10 as a component of Red Hat Enterprise Linux command line assistant; container-native-virtualization/ocp-virt-validation-checkup-rhel9 as a component of Red Hat OpenShift Virtualization 4; openshift-virtualization/ocp-virt-validation-checkup-rhel9 as a component of Red Hat OpenShift Virtualization 4; satellite/foreman-mcp-server-rhel9 as a component of Red Hat Satellite 6
- Vendor guidanceAuthoritative vendor guidance changed from remediation: access.redhat.com/CVE-2026-96760 to remediation: access.redhat.com/CVE-2026-96760.Red Hat Product Security ↗
- Before
- remediation: access.redhat.com/CVE-2026-96760
- After
- remediation: access.redhat.com/CVE-2026-96760
- Remediation statusRemediation status changed from Awaiting fix to Mitigation available.Red Hat Product Security ↗
- Before
- Awaiting fix
- After
- Mitigation available
- SeveritySeverity changed from Unknown to Critical.CISA ADP ↗
- Before
- Unknown
- After
- Critical
- CVSS scoreCVSS score changed from not recorded to 9.8 (CVSS 3.1 · CISA ADP · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).CISA ADP ↗
- Before
- not recorded
- After
- 9.8 (CVSS 3.1 · CISA ADP · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)
- ENISA EUVD mappingEUVD-2026-88465 was added to the official ENISA EUVD mapping for this CVE.ENISA EUVD ↗
- Before
- not recorded
- After
- {"euvdId":"EUVD-2026-88465"}
- Catalogue recordCVE added to the BlackTree catalogue.CNA ↗
Technical terms and abbreviations used in this report
- CVE
- Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
- CVSS
- Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
- EPSS
- Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
- CWE
- Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
- CNA
- CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
- CISA ADP
- Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
- NVD
- National Vulnerability Database: NIST's enrichment service for CVE records.
- CERT / CSIRT
- A computer security incident response team that publishes warnings or coordinates incident response.
- PoC
- Proof of concept: public material that demonstrates or helps reproduce exploitation.
- CSAF
- Common Security Advisory Framework: a machine-readable format for security advisories.
- LoTL
- Living off the land: abuse of legitimate tools or system functions during an attack.