Time-of-check Time-of-use (TOCTOU) Race Condition in yarn
| Risk | Medium |
| Patch available | YES |
| Number of vulnerabilities | 1 |
| CVE-ID | CVE-2019-15608 |
| CWE-ID | CWE-367 |
| Exploitation vector | Network |
| Public exploit | N/A |
| Vulnerable software Subscribe |
yarn Web applications / Modules and components for CMS |
| Vendor | Yarn |
Security Bulletin
This security bulletin contains one medium risk vulnerability.
1) Time-of-check Time-of-use (TOCTOU) Race Condition
EUVDB-ID: #VU34750
Risk: Medium
CVSSv3.1: 5.2 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N/E:U/RL:O/RC:C]
CVE-ID: CVE-2019-15608
CWE-ID:
CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition
Exploit availability: No
DescriptionThe 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.
MitigationInstall update from vendor's website.
Vulnerable software versionsyarn: 1.0.0 - 1.18.0
External linkshttp://github.com/yarnpkg/yarn/blob/master/CHANGELOG.md#1190
http://github.com/yarnpkg/yarn/commit/0474b8c66a8ea298f5e4dedc67b2de464297ad1c
http://hackerone.com/reports/703138
Q & A
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
