CVE-2026-52776
Trestle URLSecurityValidator SSRF allowlist bypass via IPv4-mapped IPv6 and 0.0.0.0
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
Description
Compliance-trestle (Trestle) is a tooling platform for managing compliance as code. In versions before 3.12.4 and versions 4.0.0 through 4.0.3, the URLSecurityValidator that guards trestle's remote-fetch paths against server-side request forgery can be bypassed to reach loopback, link-local, cloud-metadata, and internal network endpoints it was designed to block. The blocklist does not canonicalize IPv4-mapped IPv6 literals such as [::ffff:169.254.169.254], which resolve to IPv6Address objects that never match the blocked IPv4 ranges, and it does not block the unspecified address 0.0.0.0, which routes to local services on Linux and inside containers. An attacker who can supply or influence an OSCAL artifact that trestle fetches, such as a malicious profile whose imports reference one of these bypass URLs, can cause the HTTPSFetcher and SFTPFetcher paths to contact cloud instance-metadata services, loopback interfaces, or internal hosts. This issue is fixed in versions 3.12.4 and 4.1.0.
Public exploit
A reference of the record is tagged as an exploit or proof of concept: anyone can try it against an unpatched system. CISA's SSVC rates its exploitation: a proof of concept is public.
Timeline
ID reserved
By GitHub_M
- 3 months later
· 3 months later
Published
- 1 day later
· 1 day later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 4.0 | High8.6 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N |
| NVDNVD · Deferred | 4.0 | High8.6 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
- EPSS (exploitation in 30 days)
- 0.44% · top 62% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.6.
Weakness
Affected products
oscal-compass · compliance-trestle
- affected < 3.12.4
- affected >= 4.0.0, < 4.1.0
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- PyPIcompliance-trestleGHSA-h47f-gmjp-m7rr (opens in a new tab)
References (3)
- https://github.com/oscal-compass/compliance-trestle/security/advisories/GHSA-h47f-gmjp-m7rr (opens in a new tab)x_refsource_CONFIRMexploit
- https://github.com/oscal-compass/compliance-trestle/commit/5335ff873a2a68eb7de43df029bea09cadff22fd (opens in a new tab)x_refsource_MISC
- https://github.com/oscal-compass/compliance-trestle/commit/d107cd16efe8eb15d46be3c1d97f1ec73d32447c (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-h47f-gmjp-m7rr (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-52776)Record last updated .