go-chi/chi through 5.2.1 contains an IP spoofing vulnerability in the RealIP middleware (middleware/realip.go). The realIP() function reads client-controlled headers (True-Client-IP, X-Real-IP, and X-Forwarded-For) and overwrites r.RemoteAddr without verifying that the request originated from a trusted proxy. Attackers can supply arbitrary IP addresses in these headers to bypass IP-based access controls, evade rate limiting and geo-IP restrictions, and pollute audit logs. Fixed in 5.3.0.
{
"cwe_ids": [
"CWE-290"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72816.json",
"cna_assigner": "VulnCheck"
}{
"source": [
"AFFECTED_FIELD",
"DESCRIPTION"
],
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "5.3.0"
},
{
"fixed": "5.2.1"
}
]
}