{"id":"CVE-2026-88896","title":"EspoCRM before 10.0.4 is vulnerable to server-side request forgery","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 doe…","severity":"medium","cvss":5.3,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","cwe":["CWE-918"],"vendor":"espocrm","product":"espocrm","affected":["espocrm < 10.0.4"],"published":"2026-09-10","updated":"2026-09-15","sourceUpdated":"2026-09-15T15:17:26.330","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-88896","references":[{"url":"https://github.com/espocrm/espocrm/security/advisories/GHSA-xwmh-j8hf-cfqw","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/espocrm-before-10.0.4-ssrf-via-ipv6-transition-address-bypass","label":"disclosure@vulncheck.com"}],"tags":["nvd","cve.org"],"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"partial","timestamp":"2026-09-15T14:29:07.490725Z"},"epss":0.00335,"epssPercentile":0.26913,"ingestedAt":"2026-09-10T13:50:37.333Z","slug":"CVE-2026-88896","body":"## Overview\n\nEspoCRM 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":29,"depthScoreParts":{"impact":29.2,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}