Vulnerability in matrix-react-sdk (CVE-2021-21320)
Summary
Vulnerability in matrix-react-sdk (CVE-2021-21320). Risk of unauthorized operations or information disclosure. Exploitable via blob. Mitigation: upgrade to 3.15.0 or later.
Original description
The description as published by the source.
Impact
The user content sandbox can be abused to trick users into opening unexpected documents after several user interactions. The content can be opened with a blob origin from the Matrix client, so it is possible for a malicious document to access user messages and secrets.
Patches
This has been fixed by https://github.com/matrix-org/matrix-react-sdk/pull/5657, which is included in 3.15.0.
Workarounds
There are no known workarounds.
Source: OSV.dev (Open Source Vulnerabilities) NVD GitHub Advisory OSV
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2021-21320 has been found in matrix-react-sdk.
Attackers can target a specific entry point like blob over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: upgrade matrix-react-sdk to 3.15.0 or later.
If unsure, ask your IT team or search "matrix-react-sdk CVE-2021-21320" on the vendor's site.
CVE-2021-21320 (matrix-react-sdk) — CWE-345
Attack vector: remote (network-reachable)
Attack surface: blob
Patched: 3.15.0 — apply immediately
Workaround: There are no known workarounds.
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-345) exists in matrix-react-sdk. Attackers reach the vulnerable code path via blob.
Check the vendor advisory for the affected versions of matrix-react-sdk. Attack surface: blob.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 3.15.0.
Workaround: There are no known workarounds.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'matrix-react-sdk' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'matrix-react-sdk' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
matrix-react-sdkを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply temporary workaround mitigate
There are no known workarounds.パッチが適用されるまでの応急処置として、There are no known workarounds. を実施。回避策の副作用 (機能低下) を確認した上で。
-
3Apply patch patch
Upgrade matrix-react-sdk to 3.15.0ステージング環境で 3.15.0 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
4Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory nvd.nist.gov
- web github.com
- web github.com
- web github.com
- web npmjs.com