{"api_version":"1","generated_at":"2026-07-23T11:59:42+00:00","cve":"CVE-2022-39246","urls":{"html":"https://cve.report/CVE-2022-39246","api":"https://cve.report/api/cve/CVE-2022-39246.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2022-39246","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2022-39246"},"summary":{"title":"CVE-2022-39246","description":"matrix-android-sdk2 is the Matrix SDK for Android. Prior to version 1.5.1, an attacker cooperating with a malicious homeserver can construct messages appearing to have come from another person. Such messages will be marked with a grey shield on some platforms, but this may be missing in others. This attack is possible due to the key forwarding strategy implemented in the matrix-android-sdk2 that is too permissive. Starting with version 1.5.1, the default policy for accepting key forwards has been made more strict in the matrix-android-sdk2. The matrix-android-sdk2 will now only accept forwarded keys in response to previously issued requests and only from own, verified devices. The SDK now sets a `trusted` flag on the decrypted message upon decryption, based on whether the key used to decrypt the message was received from a trusted source. Clients need to ensure that messages decrypted with a key with `trusted = false` are decorated appropriately (for example, by showing a warning for such messages). As a workaroubnd, current users of the SDK can disable key forwarding in their forks using `CryptoService#enableKeyGossiping(enable: Boolean)`.","state":"PUBLIC","assigner":"security-advisories@github.com","published_at":"2022-09-28 20:15:00","updated_at":"2022-09-30 17:12:00"},"problem_types":["CWE-287","CWE-322"],"metrics":[],"references":[{"url":"https://github.com/matrix-org/matrix-android-sdk2/releases/tag/v1.5.1","name":"https://github.com/matrix-org/matrix-android-sdk2/releases/tag/v1.5.1","refsource":"MISC","tags":[],"title":"Release v1.5.1 · matrix-org/matrix-android-sdk2 · GitHub","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://github.com/matrix-org/matrix-spec-proposals/pull/3061","name":"https://github.com/matrix-org/matrix-spec-proposals/pull/3061","refsource":"MISC","tags":[],"title":"MSC3061: Sharing room keys for past messages by uhoreg · Pull Request #3061 · matrix-org/matrix-spec-proposals · GitHub","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://github.com/matrix-org/matrix-android-sdk2/security/advisories/GHSA-2pvj-p485-cp3m","name":"https://github.com/matrix-org/matrix-android-sdk2/security/advisories/GHSA-2pvj-p485-cp3m","refsource":"CONFIRM","tags":[],"title":"Impersonation via forwarded Megolm sessions · Advisory · matrix-org/matrix-android-sdk2 · GitHub","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://github.com/matrix-org/matrix-android-sdk2/commit/77df720a238d17308deab83ecaa37f7a4740a17e","name":"https://github.com/matrix-org/matrix-android-sdk2/commit/77df720a238d17308deab83ecaa37f7a4740a17e","refsource":"MISC","tags":[],"title":"Merge branch 'release/1.5.1' into develop · matrix-org/matrix-android-sdk2@77df720 · GitHub","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://www.cve.org/CVERecord?id=CVE-2022-39246","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2022-39246","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[{"cve_year":"2022","cve_id":"39246","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"a","cpe4":"matrix","cpe5":"software_development_kit","cpe6":"*","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"android","cpe12":"*","cpe13":"*"}],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"CVE_data_meta":{"ASSIGNER":"security-advisories@github.com","ID":"CVE-2022-39246","STATE":"PUBLIC","TITLE":"matrix-android-sdk2 vulnerable to impersonation via forwarded Megolm sessions"},"affects":{"vendor":{"vendor_data":[{"product":{"product_data":[{"product_name":"matrix-android-sdk2","version":{"version_data":[{"version_value":"< 1.5.1"}]}}]},"vendor_name":"matrix-org"}]}},"data_format":"MITRE","data_type":"CVE","data_version":"4.0","description":{"description_data":[{"lang":"eng","value":"matrix-android-sdk2 is the Matrix SDK for Android. 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As a workaroubnd, current users of the SDK can disable key forwarding in their forks using `CryptoService#enableKeyGossiping(enable: Boolean)`."}]},"impact":{"cvss":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"HIGH","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","version":"3.1"}},"problemtype":{"problemtype_data":[{"description":[{"lang":"eng","value":"CWE-322: Key Exchange without Entity Authentication"}]},{"description":[{"lang":"eng","value":"CWE-287: Improper Authentication"}]}]},"references":{"reference_data":[{"name":"https://github.com/matrix-org/matrix-spec-proposals/pull/3061","refsource":"MISC","url":"https://github.com/matrix-org/matrix-spec-proposals/pull/3061"},{"name":"https://github.com/matrix-org/matrix-android-sdk2/security/advisories/GHSA-2pvj-p485-cp3m","refsource":"CONFIRM","url":"https://github.com/matrix-org/matrix-android-sdk2/security/advisories/GHSA-2pvj-p485-cp3m"},{"name":"https://github.com/matrix-org/matrix-android-sdk2/commit/77df720a238d17308deab83ecaa37f7a4740a17e","refsource":"MISC","url":"https://github.com/matrix-org/matrix-android-sdk2/commit/77df720a238d17308deab83ecaa37f7a4740a17e"},{"name":"https://github.com/matrix-org/matrix-android-sdk2/releases/tag/v1.5.1","refsource":"MISC","url":"https://github.com/matrix-org/matrix-android-sdk2/releases/tag/v1.5.1"}]},"source":{"advisory":"GHSA-2pvj-p485-cp3m","discovery":"UNKNOWN"}},"nvd":{"publishedDate":"2022-09-28 20:15:00","lastModifiedDate":"2022-09-30 17:12:00","problem_types":["CWE-287","CWE-322"],"metrics":{"baseMetricV3":{"cvssV3":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"LOW","availabilityImpact":"NONE","baseScore":5.3,"baseSeverity":"MEDIUM"},"exploitabilityScore":3.9,"impactScore":1.4}},"configurations":{"CVE_data_version":"4.0","nodes":[{"operator":"OR","children":[],"cpe_match":[{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:matrix:software_development_kit:*:*:*:*:*:android:*:*","versionEndExcluding":"1.5.1","cpe_name":[]}]}]}},"legacy_mitre":{"record":null,"notes":[]}}}