CVE-2018-20995 — slice-deque
CRITICALCVE-2018-20995 is a critical-severity (CVSS 9.8) Buffer Overflow vulnerability in slice-deque. A fix is available for slice-deque — see the affected versions and patch details below.
Memory corruption slice-deque
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2018-20995 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 385,738 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
slice-dequeReal-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
Affected versions of this crate did not properly update the head and tail of the deque when inserting and removing elements from the front if, before insertion or removal, the tail of the deque was in the mirrored memory region, and if, after insertion or removal, the head of the deque is exactly at the beginning of the mirrored memory region.
An attacker that controls both element insertion and removal into the deque could put it in a corrupted state. Once the deque enters such an state, its head and tail are corrupted, but in bounds of the allocated memory. This can result in partial reads and writes, reads of uninitialized memory, reads of memory containing previously dropped objects, etc. An attacker could exploit this to alter program execution.
The flaw was corrected by properly updating the head and tail of the deque in this case.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | slice-deque | all versions | 0.1.16cargo update -p slice-deque --precise 0.1.16 |
Affected Products
slice-dequeslice-deque_projectDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for slice-deque, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update slice-deque to 0.1.16 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2018-20995 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-2018-20995 in your dependencies?
Find it across crates.io, including transitive dependencies.