SB2020031527 - Time-of-check Time-of-use (TOCTOU) Race Condition in yarn
Published: March 15, 2020 Updated: August 8, 2020
Security Bulletin ID
SB2020031527
Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Data manipulation
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Time-of-check Time-of-use (TOCTOU) Race Condition (CVE-ID: CVE-2019-15608)
The vulnerability allows a remote non-authenticated attacker to manipulate data.
The package integrity validation in yarn < 1.19.0 contains a TOCTOU vulnerability where the hash is computed before writing a package to cache. It's not computed again when reading from the cache. This may lead to a cache pollution attack.
Remediation
Install update from vendor's website.