CVE-2018-12556

Exploitation

Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.

SSVC decision

Not assessed by CISA

EPSS probability

1.77% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 76.6% of scored records. A rank, not a probability.

NVD base score

5.9 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

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

NVD analysis status

Modified. NVD last modified this record on 2026-06-17.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2019-05-16 16:12Z7 YR AGO

Last updated

2024-08-05 08:38Z2 YR AGO

Reserved

2018-06-18

Assigning CNA

mitre

Record state

PUBLISHED

Severity

Not rated by the issuing CNA

CNA CVSS vector

Not published by the issuing CNA

Weaknesses

• CWE-347Improper Verification of Cryptographic SignatureBase

Data version

5.1

Document digest

8cb4455881bbdcb703165d4192df26b739eccfac5288432cc7931887ffe66392

• github.comhttps://github.com/yarnpkg/website/commits/masterx_refsource_MISC
• seclists.org20190430 OpenPGP and S/MIME signature forgery attacks in multiple email clientshttp://seclists.org/fulldisclosure/2019/Apr/38mailing-listx_refsource_FULLDISC
• packetstormsecurity.comhttp://packetstormsecurity.com/files/152703/Johnny-You-Are-Fired.htmlx_refsource_MISC
• www.openwall.com[oss-security] 20190430 Spoofing OpenPGP and S/MIME Signatures in Emails (multiple clients)https://www.openwall.com/lists/oss-security/2019/04/30/4mailing-listx_refsource_MLIST
• github.comhttps://github.com/RUB-NDS/Johnny-You-Are-Firedx_refsource_MISC
• github.comhttps://github.com/RUB-NDS/Johnny-You-Are-Fired/blob/master/paper/johnny-fired.pdfx_refsource_MISC