Symptom164 problems· 12 reviewed

Auth and Session Failure

164 incident problems that show up as “Auth and Session Failure”.

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How to split IAM, TLS, and WAF failures into a security operations flowAn InfraTree guide that lays out the first signals to check, the CLI verification order, common misdiagnoses, and a safe recovery path when authentication, authorization, certificate, WAF, and audit log signals mix together and look like a single access failure.Security3 min read How to isolate an mTLS trust bundle mismatchAn InfraTree guide that lays out the first signals to check, the CLI verification order, common misdiagnoses, and a safe recovery path when the client certificate, server certificate, CA bundle, and sidecar reload timing differ and the handshake fails.Security3 min read How to safely diagnose a WAF 403 false positiveAn InfraTree guide that lays out the first signals to check, the CLI verification order, common misdiagnoses, and a safe recovery path when it looks like a permissions problem but a specific header, payload, or rule group is blocking legitimate requests.Security3 min read

Recommended problems

Reviewed problems first, then problems with detailed scenarios.

Actions fails only on fork PRs: Username and password requiredActions fails only on fork PRs: Username and password required is a hands-on troubleshooting drill. Know why repository secrets are not passed to pull requests from forks. pull-request-security needs to be checked by narrowing scope, recent change, and the current live signal...ReviewedCI/CDBeginner3 minFree LINUX-006The application cannot read filesA scenario that narrows down the root cause, centered on checking permissions, owner, and the execution account together, in the situation of the application being unable to read files because permissions changed after a deploy script.ReviewedLinuxIntermediate19 minFree LINUX-056SSH key is valid but included config disables PubkeyAuthentication later in the chainAuthorized keys and file permissions look healthy, yet login falls back to password because a later include file overrides the expected sshd setting.ReviewedLinuxIntermediate17 minFree LINUX-096NTP is synchronized but the hardware clock drifts back after every reboot and breaks certificatesThe running host time looks correct, but restarts reintroduce skew because the persistent hardware clock was never aligned.ReviewedLinuxIntermediate14 minFree SECURITY-005IAM role rotation leaves one batch worker using stale credentialsMost services refresh correctly, but one worker process keeps using cached credentials and starts failing scheduled jobs.ReviewedSecurityIntermediate20 minPro SECURITY-016MFA enforcement skipped for legacy admin endpointMFA enforcement skipped for legacy admin endpoint is a hands-on troubleshooting drill. The main login path correctly enforces MFA, but a secondary admin route still accepts a weaker path. Identity and Access Management needs to be checked by narrowing scope, recent change, and...ReviewedSecurityBeginner14 minFree

All problems (164)

403 Forbidden: login works but one admin action is refused (vs 401)403 Forbidden: login works but one admin action is refused (vs 401) is a hands-on troubleshooting drill. Tell authentication failures (401) from authorization failures (403). Identity And Access needs to be checked by narrowing scope, recent change, and the current live signal...ReviewedSecurityBeginner3 minFree Actions fails only on fork PRs: Username and password requiredActions fails only on fork PRs: Username and password required is a hands-on troubleshooting drill. Know why repository secrets are not passed to pull requests from forks. pull-request-security needs to be checked by narrowing scope, recent change, and the current live signal...ReviewedCI/CDBeginner3 minFree jwt expired (401): every request fails after about an hour in the appjwt expired (401): every request fails (Auth and Session Failure) is a hands-on troubleshooting drill. Recognise token expiry and the missing refresh step. token-validation needs to be checked by narrowing scope, recent change, and the current live signal before rollback. 실무에서...ReviewedSecurityBeginner3 minFree SECURITY-058OAuth device code session remains active after user offboardingThe user account is disabled, but a previously authorized device code flow keeps working because token revocation and downstream session invalidation were not linked tightly enough.ReviewedSecurityIntermediate20 minFree SECURITY-056Secrets Manager rotation updates the writer credential but read replicas still use the old secretRotation completes successfully on the primary path, yet one read-side workload keeps failing because its secret retrieval or cache path was never included in the rotation design.ReviewedSecurityIntermediate21 minFree LINUX-096NTP is synchronized but the hardware clock drifts back after every reboot and breaks certificatesThe running host time looks correct, but restarts reintroduce skew because the persistent hardware clock was never aligned.ReviewedLinuxIntermediate14 minFree LINUX-006The application cannot read filesA scenario that narrows down the root cause, centered on checking permissions, owner, and the execution account together, in the situation of the application being unable to read files because permissions changed after a deploy script.ReviewedLinuxIntermediate19 minFree SECURITY-025Locked-down file permission hides SSH authorized_keys from user sessionLocked-down file permission hides SSH authorized_keys from user session is a hands-on troubleshooting drill. The authorized key exists, but the home directory ownership or mode makes the SSH daemon ignore it. Identity and Access Management needs to be checked by narrowing scop...ReviewedSecurityBeginner14 minFree LINUX-056SSH key is valid but included config disables PubkeyAuthentication later in the chainAuthorized keys and file permissions look healthy, yet login falls back to password because a later include file overrides the expected sshd setting.ReviewedLinuxIntermediate17 minFree SECURITY-016MFA enforcement skipped for legacy admin endpointMFA enforcement skipped for legacy admin endpoint is a hands-on troubleshooting drill. The main login path correctly enforces MFA, but a secondary admin route still accepts a weaker path. Identity and Access Management needs to be checked by narrowing scope, recent change, and...ReviewedSecurityBeginner14 minFree CORS blocks the new admin frontend's API calls with credentialsCORS blocks the new admin frontend's API calls with credentials is a hands-on troubleshooting drill. Read the browser's CORS error precisely and return the right headers for credentialed requests. WAF and AppSec Controls needs to be checked by narrowing scope, recent change, a...ReviewedSecurityBeginner14 minFree LINUX-017Only the operations automation account fails to run a command due to a sudoers rule differenceCovers a situation where human accounts work but only the automation account is blocked on a specific command due to different permissions.LinuxIntermediate19 minFree SECURITY-097Conditional access trusts the compliant device claim but the token was minted before the device fell out of complianceThe policy is sound, yet a risky session survives because token lifetime outlasts the compliance state transition the team expected to revoke it instantly.SecurityIntermediate15 minFree SECURITY-086Federated logout succeeds in the IdP but leaves the local admin session alive on the legacy appThe user appears signed out globally, but the legacy admin panel still accepts requests because its local session invalidation is not coupled to federation logout.SecurityIntermediate16 minFree SECURITY-068MFA-enforced sudo flow breaks non-interactive automation on one hostThe stronger policy is correct for humans, but the service account path now fails because the exempt automation group was never applied consistently.SecurityIntermediate16 minFree SECURITY-071OAuth login fails after a vanity-domain cutoverThe app and IdP are healthy, but authentication loops because the new branded callback path does not exactly match the registered redirect URI set.SecurityIntermediate16 minFree LINUX-075pam_faillock keeps accounts blocked after LDAP recoveryDirectory authentication is healthy again, but users still cannot log in because the host-local lock records survived the upstream outage.LinuxIntermediate16 minFree NETWORK-107DHCP relay uses the correct helper address but the source interface belongs to the wrong VRF so replies never returnDiscover messages leave the switch, yet offers vanish because the server replies into a routing context that has no path back to the client segment.NetworkIntermediate17 minFree SECURITY-076EKS IRSA token file becomes unreadable after a sidecar changes the shared volume ownershipThe role mapping is correct, but the application cannot assume it because the projected token path no longer matches the runtime user permissions after a sidecar update.SecurityIntermediate17 minFree SECURITY-059Conditional access blocks the break-glass admin path during a device compliance incidentThe stronger policy makes sense normally, but the emergency access route now fails because it was never carved out from the same device compliance requirements.SecurityIntermediate18 minFree