CVE-2021-29938
HIGHCVE-2021-29938 is a high-severity (CVSS 7.5) CWE-415 vulnerability in slice-deque_project slice-deque. 1 public exploit reference exists, so weaponization risk is real. O3 Security detects and blocks CVE-2021-29938 exploitation at runtime via eBPF exploit-chain detection and L7 egress monitoring, even on unpatched systems.
An issue was discovered in the slice-deque crate through 2021-02-19 for Rust. A double drop can occur in SliceDeque::drain_filter upon a panic in a predicate function.
Description
An issue was discovered in the slice-deque crate through 2021-02-19 for Rust. A double drop can occur in SliceDeque::drain_filter upon a panic in a predicate function.
Affected Products
slice-dequeslice-deque_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
Vendor / applianceDetect
Inventory every slice-deque_project slice-deque deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for exploitation at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.
Remediation status
No patch has shipped for CVE-2021-29938 yet — track the slice-deque_project slice-deque advisory for a fixed release and apply the workarounds below in the meantime.
Mitigate without a patch
Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.
How O3 protects you
O3 detects and blocks CVE-2021-29938 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.
Tailored to CVE-2021-29938. 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-2021-29938 being exploited in your environment?
O3's eBPF runtime sensors and L7 egress monitoring detect and block the CVE-2021-29938 exploit chain at execution — protecting unpatched and end-of-life systems until the vendor patch is applied.