The mail gem before 2.5.5 for Ruby (aka A Really Ruby Mail Library) is vulnerable to SMTP…
Priority LOW 33CWE-93Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- Low · Low · None
- Fix status
- Partial Red Hat: 3 without a fix
Attack profile from CVSS 3.0 · NVD. Fix status from CNA, GitHub and Red Hat.
Summary
The mail gem before 2.5.5 for Ruby (aka A Really Ruby Mail Library) is vulnerable to SMTP command injection via CRLF sequences in a RCPT TO or MAIL FROM command, as demonstrated by CRLF sequences immediately before and after a DATA substring.
Why it matters now
EPSS 0.03396 88th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial mail (RubyGems): 2.5.5Red Hat: 3 without a fix
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
| — | mail (RubyGems) | before 2.5.5 | 2.5.5 | Patch available | GHSA-q86f-fmqf-qrf6 |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
- mail (RubyGems) Vendor— Affected before 2.5.5 Fixed in 2.5.5 Patch available GHSA-q86f-fmqf-qrf6
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:mail_project:mail:*:*:*:*:*:ruby:*:* | up to 2.5.4 | Vulnerable | Mail Project |
- cpe:2.3:a:mail_project:mail:*:*:*:*:*:ruby:*:* Versions up to 2.5.4 Vulnerable ·Mail Project
Remediation
- Fix · GHSA-q86f-fmqf-qrf6 mail (RubyGems) Fixed in 2.5.5 Advisory →
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| CloudForms Management Engine 5 | Affected | No fix planned: Will not fix |
| Red Hat Software Collections | Affected | No fix planned: Will not fix |
| Red Hat Subscription Asset Manager | Affected | No fix planned: Will not fix |
Not affected: 1 product
- Red Hat Software Collections
Timeline
- 2026-10-02 Threatist record created from CVE-2015-9097
- 2026-10-03 Alias added: GHSA-q86f-fmqf-qrf6
References
Advisory 8
- https://github.com/mikel/mail/pull/1097
- https://hackerone.com/reports/137631
- http://openwall.com/lists/oss-security/2015/12/11/3
- https://rubysec.com/advisories/mail-OSVDB-131677
- https://github.com/rubysec/ruby-advisory-db/issues/215
- http://www.mbsd.jp/Whitepaper/smtpi.pdf
- https://nvd.nist.gov/vuln/detail/CVE-2015-9097
- https://github.com/advisories/GHSA-q86f-fmqf-qrf6
Sources
- CVE-2015-9097 · CVE Program
- CVE-2015-9097 · NVD
- FIRST EPSS
- GHSA-q86f-fmqf-qrf6 · GitHub Advisory Database · CC BY 4.0
- CVE-2015-9097 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences