CVE-2024-34353 is a medium-severity (CVSS 5.5) CWE-532 vulnerability in matrix-sdk-crypto. A fix is available for matrix-sdk-crypto — see the affected versions and patch details below.
matrix-sdk-crypto contains a log exposure of private key of the server-side key backup
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2024-34353.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2024-34353 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,238 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
matrix-sdk-cryptoReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.
Description
The matrix-sdk-crypto crate, part of the Matrix Rust SDK project, is an implementation of a Matrix end-to-end encryption state machine in Rust. In Matrix, the server-side key backup stores encrypted copies of Matrix message keys. This facilitates key sharing between a user's devices and provides a redundant copy in case all devices are lost. The key backup uses asymmetric
cryptography, with each server-side key backup assigned a unique public-private key pair. Due to a logic bug introduced in commit 71136e44c03c79f80d6d1a2446673bc4d53a2067, matrix-sdk-crypto version 0.7.0 will sometimes log the private part of the backup key pair to Rust debug logs (using the tracing crate). This issue has been resolved in matrix-sdk-crypto version 0.7.1. No known workarounds are available.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | matrix-sdk-crypto | ≥ 0.7.0&&< 0.7.1 | 0.7.1cargo update -p matrix-sdk-crypto --precise 0.7.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for matrix-sdk-crypto, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update matrix-sdk-crypto to 0.7.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-34353 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2024-34353 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2024-34353. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2024-34353 in your dependencies?
O3 Security finds CVE-2024-34353 across crates.io dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.