EspoCRM before 10.0.4 SSRF via IPv6 Transition Address Bypass
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- None · Low · None
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA.
Summary
EspoCRM before 10.0.4 is vulnerable to server-side request forgery. HostCheck::ipAddressIsNotInternal(), which validates outbound URLs to block requests to internal/private IP addresses, strips ::ffff: (IPv4-mapped IPv6) prefixes but does not recognize IPv6 transition addresses that embed private IPv4 addresses: NAT64 (64:ff9b::), 6to4 (2002::), and Teredo (2001:0000::). An attacker who controls a domain with AAAA records pointing to such transition addresses can bypass both the internal-host validation and the CURLOPT_RESOLVE IP-pinning check, causing EspoCRM to issue outbound requests to internal network services. Affected paths include POST /Attachment/fromImageUrl, reachable by any authenticated user with attachment access, and outbound webhook delivery, which requires an admin or API user.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA espocrm (espocrm) Fixed in 10.0.4
Timeline
- 2026-10-02 Threatist record created from CVE-2026-88896
- 2026-10-03 Alias added: GHSA-p98c-469w-949w
References
More espocrm vulnerabilities
- TI-2020-19229 EspoCRM 5.7.0 < 5.9.0 - Two-Factor Authentication Bypass via Auth Token Reuse Between Accounts with Identical Passwords CVSS 4.0HIGH 8.6
- TI-2026-26036 Path traversal in espocrm CVSS 3.1CRITICAL 9.1
- TI-2025-32670 EspoCRM vulnerable to LDAP Injection through Improper Neutralization of Special Elements CVSS 3.1MEDIUM 6.5
- TI-2026-26112 EspoCRM has Admin TemplateManager path traversal that allows arbitrary file read write and delete CVSS 3.1HIGH 7.2
- TI-2025-23468 EspoCRM vulnerable to HTML Injection into phishing, which may lead to account takeover CVSS 4.0HIGH 7.0
- TI-2026-26120 EspoCRM: Stored XSS via SVG attachment loading same-origin JavaScript CVSS 3.1MEDIUM 6.8
Sources
- CVE-2026-88896 · CVE Program
- CVE-2026-88896 · NVD
- FIRST EPSS
- GHSA-p98c-469w-949w · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences