CVE-2021-29934 is a high-severity (CVSS 7.3) Out-of-bounds Read vulnerability in uu_od. 1 public exploit reference exists, so weaponization risk is real. A fix is available for uu_od — see the affected versions and patch details below.
Out of bounds read in uu_od
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2021-29934 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 385,987 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
uu_odReal-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
An issue was discovered in PartialReader in the uu_od crate before 0.0.4 for Rust. Attackers can read the contents of uninitialized memory locations via a user-provided Read operation.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | uu_od | all versions | 0.0.4cargo update -p uu_od --precise 0.0.4 |
Affected Products
uu oduu_od_projectResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for uu_od, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update uu_od to 0.0.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-29934 is resolved across your whole dependency graph.
Workarounds
Constrain what reaches the vulnerable code: limit the size and shape of untrusted input, isolate the affected component in a sandboxed or least-privileged process, and enable the platform's memory-safety mitigations (ASLR, stack protector, hardened allocator) so an out-of-bounds access is more likely to fail closed than to be exploitable.
Frequently Asked Questions
Is CVE-2021-29934 in your dependencies?
Find it across crates.io, including transitive dependencies.