{"id":"CVE-2026-45274","state":"PUBLISHED","title":"MyBooks: Unauthenticated Registration Bypass via Missing Server-Side ALLOW_REGISTER Enforcement","description":"MyBooks is anebook management web server also known as Talebook. In 3.41.2 and earlier, the SignUp.post handler for POST /api/user/sign_up in webserver/handlers/user.py does not enforce the ALLOW_REGISTER configuration flag, even though the frontend hides registration controls when the flag is false. An unauthenticated remote attacker can call the endpoint directly and create a valid account on an instance whose administrator disabled public registration. The process_auth_header function in webserver/handlers/base.py also does not verify the account's active flag, so the newly created and unactivated account can authenticate immediately and access user-level API functionality. The bypass defeats the intended account-creation policy and can supply the low-privilege account required by related authorization vulnerabilities. This issue is fixed in version 3.42.0.","publishedAt":"2026-08-19T14:38:58.849Z","updatedAt":"2026-08-19T15:23:12.071Z","severity":{"score":6.9,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["PoxenStudio talebook"],"affected":[{"vendor":"PoxenStudio","product":"talebook","versions":[{"version":"< 3.42.0","status":"affected"}]}],"references":["https://github.com/PoxenStudio/mybooks/security/advisories/GHSA-3q85-5vj5-qx5v","https://github.com/PoxenStudio/mybooks/commit/a1780c98b00566af7da2fc099fe38500efc02e92","https://github.com/PoxenStudio/mybooks/releases/tag/3.42.0"],"weaknesses":["CWE-602"],"ingestedAt":"2026-10-29T20:12:07.131Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/45xxx/CVE-2026-45274.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-45274","state":"PUBLISHED","datePublished":"2026-08-19T14:38:58.849Z","dateUpdated":"2026-08-19T15:23:12.071Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-05-11T18:41:13.156Z"},"containers":{"cna":{"title":"MyBooks: Unauthenticated Registration Bypass via Missing Server-Side ALLOW_REGISTER Enforcement","descriptions":[{"lang":"en","value":"MyBooks is anebook management web server also known as Talebook. In 3.41.2 and earlier, the SignUp.post handler for POST /api/user/sign_up in webserver/handlers/user.py does not enforce the ALLOW_REGISTER configuration flag, even though the frontend hides registration controls when the flag is false. An unauthenticated remote attacker can call the endpoint directly and create a valid account on an instance whose administrator disabled public registration. The process_auth_header function in webserver/handlers/base.py also does not verify the account's active flag, so the newly created and unactivated account can authenticate immediately and access user-level API functionality. The bypass defeats the intended account-creation policy and can supply the low-privilege account required by related authorization vulnerabilities. This issue is fixed in version 3.42.0."}],"affected":[{"vendor":"PoxenStudio","product":"talebook","versions":[{"version":"< 3.42.0","status":"affected"}]}],"references":[{"url":"https://github.com/PoxenStudio/mybooks/security/advisories/GHSA-3q85-5vj5-qx5v","name":"https://github.com/PoxenStudio/mybooks/security/advisories/GHSA-3q85-5vj5-qx5v","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/PoxenStudio/mybooks/commit/a1780c98b00566af7da2fc099fe38500efc02e92","name":"https://github.com/PoxenStudio/mybooks/commit/a1780c98b00566af7da2fc099fe38500efc02e92","tags":["x_refsource_MISC"]},{"url":"https://github.com/PoxenStudio/mybooks/releases/tag/3.42.0","name":"https://github.com/PoxenStudio/mybooks/releases/tag/3.42.0","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"LOW","vulnIntegrityImpact":"LOW","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":6.9,"baseSeverity":"MEDIUM","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-602","lang":"en","description":"CWE-602: Client-Side Enforcement of Server-Side Security","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-08-19T14:38:58.849Z"},"source":{"advisory":"GHSA-3q85-5vj5-qx5v","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/PoxenStudio/mybooks/security/advisories/GHSA-3q85-5vj5-qx5v","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-19T15:22:55.400640Z","id":"CVE-2026-45274","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-19T15:23:12.071Z"}}]}}}