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.
[
{
"product": "yarn",
"vendor": "n/a",
"versions": [
{
"status": "affected",
"version": "Fixed in 1.19.0"
}
]
}
]