{"id":"CVE-2026-24398","aliases":["EUVD-2026-4774","GHSA-r354-f388-2fhh"],"status":"published","title":"Hono's IPv4 address validation bypass in IP Restriction Middleware allows IP spoofing","description":"Hono is a Web application framework that provides support for any JavaScript runtime. Prior to version 4.11.7, IP Restriction Middleware in Hono is vulnerable to an IP address validation bypass. The `IPV4_REGEX` pattern and `convertIPv4ToBinary` function in `src/utils/ipaddr.ts` do not properly validate that IPv4 octet values are within the valid range of 0-255, allowing attackers to craft malformed IP addresses that bypass IP-based access controls. Version 4.11.7 contains a patch for the issue.","severity":{"version":"3.1","score":4.8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00342,"percentile":0.28105,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-185"],"published":"2026-01-27T19:01:43Z","modified":"2026-10-28T02:31:03Z","fixes":[{"ecosystem":"npm","package":"hono","fixed_in":["4.11.7"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"hono","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"4.11.7"}]}]},{"source":"osv","ecosystem":"npm","package":"hono","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"4.11.7"}]}]}],"products":[{"vendor":"hono","product":"hono"},{"vendor":"honojs","product":"hono"}],"references":[{"url":"https://github.com/honojs/hono/security/advisories/GHSA-r354-f388-2fhh","tags":["x_refsource_CONFIRM","Vendor Advisory","advisory","web"]},{"url":"https://github.com/honojs/hono/commit/edbf6eea8e6c26a3937518d4ed91d8666edeec37","tags":["x_refsource_MISC","Patch","fix","web"]},{"url":"https://github.com/honojs/hono/releases/tag/v4.11.7","tags":["x_refsource_MISC","Release Notes","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-24398","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-r354-f388-2fhh"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/24xxx/CVE-2026-24398.json","tags":["advisory"]},{"url":"https://github.com/honojs/hono","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-24398","title":"Hono's IPv4 address validation bypass in IP Restriction Middleware allows IP spoofing","description":"Hono is a Web application framework that provides support for any JavaScript runtime. Prior to version 4.11.7, IP Restriction Middleware in Hono is vulnerable to an IP address validation bypass. The `IPV4_REGEX` pattern and `convertIPv4ToBinary` function in `src/utils/ipaddr.ts` do not properly validate that IPv4 octet values are within the valid range of 0-255, allowing attackers to craft malformed IP addresses that bypass IP-based access controls. Version 4.11.7 contains a patch for the issue.","status":"published","published":"2026-01-27T19:06:42.792Z","modified":"2026-01-27T19:20:35.594Z","cvss":[{"version":"3.1","score":4.8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-185"],"updated_at":"2026-11-02T14:19:50.575061Z"}],"euvd":[{"id":"EUVD-2026-4774","description":"Hono is a Web application framework that provides support for any JavaScript runtime. Prior to version 4.11.7, IP Restriction Middleware in Hono is vulnerable to an IP address validation bypass. The `IPV4_REGEX` pattern and `convertIPv4ToBinary` function in `src/utils/ipaddr.ts` do not properly validate that IPv4 octet values are within the valid range of 0-255, allowing attackers to craft malformed IP addresses that bypass IP-based access controls. Version 4.11.7 contains a patch for the issue.","status":"published","published":"2026-01-27T19:06:42Z","modified":"2026-01-27T19:20:35Z","cvss":[{"version":"3.1","score":4.8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T19:48:46.818498Z"}],"ghsa":[{"id":"GHSA-r354-f388-2fhh","title":"Hono IPv4 address validation bypass in IP Restriction Middleware allows IP spoofing","description":"## Summary\n\nIP Restriction Middleware in Hono is vulnerable to an IP address validation bypass. The `IPV4_REGEX` pattern and `convertIPv4ToBinary` function in `src/utils/ipaddr.ts` do not properly validate that IPv4 octet values are within the valid range of 0-255, allowing attackers to craft malformed IP addresses that bypass IP-based access controls.\n\n## Details\n\nThe vulnerability exists in two components:\n\n1. **Permissive regex pattern:** The `IPV4_REGEX (/^[0-9]{0,3}\\.[0-9]{0,3}\\.[0-9]{0,3}\\.[0-9]{0,3}$/)` accepts octet values greater than 255 (e.g., `999`).\n2. **Unsafe binary conversion:** The `convertIPv4ToBinary` function does not validate octet ranges before performing bitwise operations. When an octet exceeds 255, it overflows into adjacent octets during the bit-shift calculation.\n\nFor example, the IP address `1.2.2.355` is accepted and converts to the same binary value as 1.2.3.99:\n\n* `355` = `256 + 99` = `0x163`\n* After bit-shifting: `(1 \u003c\u003c 24) + (2 \u003c\u003c 16) + (2 \u003c\u003c 8) + 355` = `0x01020363` = `1.2.3.99`\n\n## Impact\n\nAn attacker can bypass IP-based restrictions by crafting malformed IP addresses:\n\n* **Blocklist bypass:** If `1.2.3.0/24` is blocked, an attacker can use `1.2.2.355` (or similar) to bypass the restriction.\n* **Allowlist bypass:** Requests from unauthorized IP ranges may be incorrectly permitted.\n\nThis is exploitable when the application relies on client-provided IP addresses (e.g., `X-Forwarded-For header`) for access control decisions.\n\n## Affected Components\n\n* IP Restriction Middleware\n* `src/utils/ipaddr.ts`: `IPV4_REGEX`, `convertIPv4ToBinary`, `distinctRemoteAddr`","status":"published","published":"2026-01-27T19:01:43Z","modified":"2026-01-29T03:39:03Z","cvss":[{"version":"3.1","score":4.8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-185"],"updated_at":"2026-11-02T14:39:20.563096Z"}],"nvd":[{"id":"CVE-2026-24398","description":"Hono is a Web application framework that provides support for any JavaScript runtime. Prior to version 4.11.7, IP Restriction Middleware in Hono is vulnerable to an IP address validation bypass. The `IPV4_REGEX` pattern and `convertIPv4ToBinary` function in `src/utils/ipaddr.ts` do not properly validate that IPv4 octet values are within the valid range of 0-255, allowing attackers to craft malformed IP addresses that bypass IP-based access controls. Version 4.11.7 contains a patch for the issue.","status":"published","published":"2026-01-27T19:16:16.363Z","modified":"2026-06-17T10:23:00.35Z","cvss":[{"version":"3.1","score":4.8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium","assessor":"secondary"},{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-185"],"updated_at":"2026-11-02T14:12:04.769088Z"}],"osv":[{"id":"CVE-2026-24398","title":"Hono's IPv4 address validation bypass in IP Restriction Middleware allows IP spoofing","description":"Hono is a Web application framework that provides support for any JavaScript runtime. Prior to version 4.11.7, IP Restriction Middleware in Hono is vulnerable to an IP address validation bypass. The `IPV4_REGEX` pattern and `convertIPv4ToBinary` function in `src/utils/ipaddr.ts` do not properly validate that IPv4 octet values are within the valid range of 0-255, allowing attackers to craft malformed IP addresses that bypass IP-based access controls. Version 4.11.7 contains a patch for the issue.","status":"published","published":"2026-01-27T19:06:42.792Z","modified":"2026-10-28T02:31:03.488638Z","cvss":[{"version":"3.1","score":4.8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-185"],"updated_at":"2026-11-02T15:44:59.079784Z"},{"id":"GHSA-r354-f388-2fhh","title":"Hono IPv4 address validation bypass in IP Restriction Middleware allows IP spoofing","description":"## Summary\n\nIP Restriction Middleware in Hono is vulnerable to an IP address validation bypass. The `IPV4_REGEX` pattern and `convertIPv4ToBinary` function in `src/utils/ipaddr.ts` do not properly validate that IPv4 octet values are within the valid range of 0-255, allowing attackers to craft malformed IP addresses that bypass IP-based access controls.\n\n## Details\n\nThe vulnerability exists in two components:\n\n1. **Permissive regex pattern:** The `IPV4_REGEX (/^[0-9]{0,3}\\.[0-9]{0,3}\\.[0-9]{0,3}\\.[0-9]{0,3}$/)` accepts octet values greater than 255 (e.g., `999`).\n2. **Unsafe binary conversion:** The `convertIPv4ToBinary` function does not validate octet ranges before performing bitwise operations. When an octet exceeds 255, it overflows into adjacent octets during the bit-shift calculation.\n\nFor example, the IP address `1.2.2.355` is accepted and converts to the same binary value as 1.2.3.99:\n\n* `355` = `256 + 99` = `0x163`\n* After bit-shifting: `(1 \u003c\u003c 24) + (2 \u003c\u003c 16) + (2 \u003c\u003c 8) + 355` = `0x01020363` = `1.2.3.99`\n\n## Impact\n\nAn attacker can bypass IP-based restrictions by crafting malformed IP addresses:\n\n* **Blocklist bypass:** If `1.2.3.0/24` is blocked, an attacker can use `1.2.2.355` (or similar) to bypass the restriction.\n* **Allowlist bypass:** Requests from unauthorized IP ranges may be incorrectly permitted.\n\nThis is exploitable when the application relies on client-provided IP addresses (e.g., `X-Forwarded-For header`) for access control decisions.\n\n## Affected Components\n\n* IP Restriction Middleware\n* `src/utils/ipaddr.ts`: `IPV4_REGEX`, `convertIPv4ToBinary`, `distinctRemoteAddr`","status":"published","published":"2026-01-27T19:01:43Z","modified":"2026-09-10T03:50:59.119404609Z","cvss":[{"version":"3.1","score":4.8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-185"],"updated_at":"2026-11-02T15:46:55.122811Z"}]}}