SSRF in Espocrm
CVE-2026-88896
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.
Vulnerability class: SSRF (Server-Side Request Forgery)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.
EPSS exploit prediction
EPSS: 0.004 (30.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 31st percentile — 30.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
Weakness classification (CWE)
References
- github.com/espocrm/espocrm/security/advisories/GHSA-xwmh-j8hf-cfqw (vendor-advisory)
- www.vulncheck.com/advisories/espocrm-before-10.0.4-ssrf-via-ipv6-transition-add… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-88896?
- CVE-2026-88896 is a medium-severity vulnerability in Espocrm, classified under Server-Side Request Forgery (SSRF). CVSS score: 5.3/10. Published 2026-09-10.
- How severe is CVE-2026-88896?
- Medium severity. CVSS v3 base score is 5.3 out of 10.