CVE-2018-12556
The signature verification routine in install.sh in yarnpkg/website through 2018-06-05 only verifies that the yarn release is signed by any (arbitrary) key in the local keyring of the user, and does not pin the signature to the yarn release key, which…
Does this matter?
Lower severity and a low EPSS score (1.77%). Track it; it rarely justifies an emergency change on its own.
Description
The signature verification routine in install.sh in yarnpkg/website through 2018-06-05 only verifies that the yarn release is signed by any (arbitrary) key in the local keyring of the user, and does not pin the signature to the yarn release key, which allows remote attackers to sign tampered yarn release packages with their own key.
- CVSS 3.0
- 5.9 MEDIUMCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
- EPSS
- 1.77% probability · 78th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-347
- Affected
- yarnpkg/website
- Source
- cve@mitre.org
EPSS 1.8% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://packetstormsecurity.com/files/152703/Johnny-You-Are-Fired.htmlThird Party Advisory, VDB Entry
- http://seclists.org/fulldisclosure/2019/Apr/38Mailing List, Third Party Advisory
- https://github.com/RUB-NDS/Johnny-You-Are-FiredThird Party Advisory
- https://github.com/RUB-NDS/Johnny-You-Are-Fired/blob/master/paper/johnny-fired.pdfThird Party Advisory
- https://github.com/yarnpkg/website/commits/masterThird Party Advisory
- https://www.openwall.com/lists/oss-security/2019/04/30/4Mailing List, Third Party Advisory
- http://packetstormsecurity.com/files/152703/Johnny-You-Are-Fired.htmlThird Party Advisory, VDB Entry
- http://seclists.org/fulldisclosure/2019/Apr/38Mailing List, Third Party Advisory
- https://github.com/RUB-NDS/Johnny-You-Are-FiredThird Party Advisory
- https://github.com/RUB-NDS/Johnny-You-Are-Fired/blob/master/paper/johnny-fired.pdfThird Party Advisory
- https://github.com/yarnpkg/website/commits/masterThird Party Advisory
- https://www.openwall.com/lists/oss-security/2019/04/30/4Mailing List, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.