CVE-2018-20993 — Uncontrolled recursion leads to abort in...

HIGH

Uncontrolled recursion leads to abort in deserialization

Published September 17, 2018Updated November 8, 2023Source: osv

Summary

Affected versions of this crate did not prevent deep recursion while deserializing data structures. This allows an attacker to make a YAML file with deeply nested structures that causes an abort while deserializing it. The flaw was corrected by checking the recursion depth. Note: `clap 2.33` is not affected by this because it uses `yaml-rust` in a way that doesn't trigger the vulnerability. More specifically: 1. The input to the YAML parser is always trusted - is included at compile time via `include_str!`. 2. The nesting level is never deep enough to trigger the overflow in practice (at most 5).

Advisory Timeline

First published September 17, 2018 (2947 days ago).
Last revised November 8, 2023 — 1878 days after initial publication.

Remediation

Upgrade to the fixed version using your package manager.

Cargo

Update yaml-rust to 0.4.1 or later

cargo update -p yaml-rust --precise 0.4.1

After upgrading, run your dependency scanner again to confirm the vulnerability is resolved.

Affected Packages (1)

Affects 1 ecosystem: crates.io (1).

Package	Ecosystem	Affected	Fixed In
yaml-rust	crates.io	All versions	0.4.1

CVSS Score Breakdown

What the CVSS (Common Vulnerability Scoring System) 7.5 score means for each attack dimension.

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

Frequently Asked Questions

What is CVE-2018-20993?: Uncontrolled recursion leads to abort in deserialization This vulnerability has been assigned a severity rating of HIGH (CVSS score: 7.5/10).
How do I check if my project is affected by CVE-2018-20993?: CVE-2018-20993 affects yaml-rust. Use GeekWala's free vulnerability scanner to check your dependencies against CVE-2018-20993 and 200,000+ other known vulnerabilities.

Severity & Exploitability

CVSS Score

7.5

High exploitability or significant impact. Prioritize remediation within days.

Also Known As

RUSTSEC-2018-0006

GHSA-hv87-47h9-jcvq

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