CVE-2026-6322: fast-uri vulnerable to host confusion via percent-encoded authority delimiters
Noroxi assessment
Priority: Monitor (action score 30/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.51% (FIRST EPSS).
- Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
- According to CISA the attack is automatable: targets can be found by mass scanning.
- Fixed version: fast-uri fast-uri 3.1.2.
Low priority for now. Upgrade to fast-uri fast-uri 3.1.2 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
fast-uri normalize() decoded percent-encoded authority delimiters inside the host component and then re-emitted them as raw delimiters during serialization. A host that combined an allowed domain, an encoded at-sign, and a different domain was re-emitted with the at-sign as a raw userinfo separator, changing the URI's authority to the second domain. Applications that normalize untrusted URLs before host allowlist checks, redirect validation, or outbound request routing can be steered to a different authority than the input appeared to specify. Versions <= 3.1.1 are affected. Update to 3.1.2 or later.
- Published
- May 5, 2026
- Updated
- Sep 10, 2026
- EPSS
- 0.5% · 43th percentile
- CWE
- CWE-436
Report tools
Action score
30
Monitor
Low priority for now.
- CVSS
- 30 / 40 · 7.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.5%
CISA SSVC decision
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · openjs
- 7.5
- NVD has not scored this yet; the score shown is the CNA’s.
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| openjsf | fast-uri | cpe:2.3:a:openjsf:fast-uri |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- openjsf fast-uribefore 3.1.2
Versions reported by the vendor
Affected version ranges reported by the assigning authority (openjs). Independent of NVD's CPE analysis and usually ahead of it.
fast-uri fast-uri
- 3.1.2not affected
- before 3.1.2affected · semver
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | node-ajv | from 0 | — |
| Debian:14 | node-ajv | before 8.20.0~ds+~cs6.1.3-1 | 8.20.0~ds+~cs6.1.3-1 |
| npm | fast-uri | from 3.0.0 · before 3.1.2 | 3.1.2 |
| npm | fast-uri | before 2.4.1 | 2.4.1 |
| Red Hat:ansible_automation_platform_developer:2.6::el9 | automation-controller | before 0:4.7.13-2.el9ap | 0:4.7.13-2.el9ap |
| Red Hat:ansible_automation_platform_developer:2.6::el9 | automation-controller-cli | before 0:4.7.13-2.el9ap | 0:4.7.13-2.el9ap |
| Red Hat:ansible_automation_platform_developer:2.6::el9 | python3.12-urllib3 | before 0:2.7.0-1.el9ap | 0:2.7.0-1.el9ap |
| Red Hat:ansible_automation_platform:2.6::el9 | automation-controller-server | before 0:4.7.13-2.el9ap | 0:4.7.13-2.el9ap |
| Red Hat:ansible_automation_platform:2.6::el9 | automation-controller-ui | before 0:4.7.13-2.el9ap | 0:4.7.13-2.el9ap |
| Red Hat:ansible_automation_platform:2.6::el9 | automation-controller-venv-tower | before 0:4.7.13-2.el9ap | 0:4.7.13-2.el9ap |
| Red Hat:ansible_automation_platform:2.6::el9 | automation-platform-ui | before 0:2.6.10-1.el9ap | 0:2.6.10-1.el9ap |
| Red Hat:ansible_automation_platform:2.6::el9 | python3.12-pyjwt | before 0:2.13.0-1.el9ap | 0:2.13.0-1.el9ap |
| Red Hat:ansible_automation_platform:2.6::el9 | python3.12-pyjwt+crypto | before 0:2.13.0-1.el9ap | 0:2.13.0-1.el9ap |
| Red Hat:ansible_automation_platform:2.6::el9 | python3.12-pysequoia | before 0:0.1.34-1.el9ap | 0:0.1.34-1.el9ap |
| Red Hat:ansible_automation_platform:2.6::el9 | python3.12-pysequoia-debuginfo | before 0:0.1.34-1.el9ap | 0:0.1.34-1.el9ap |
| Red Hat:ansible_automation_platform:2.6::el9 | python3.12-pysequoia-debugsource | before 0:0.1.34-1.el9ap | 0:0.1.34-1.el9ap |
| Red Hat:enterprise_linux:10.2 | rh-podman-desktop | before 0:1.1.1-1.el10_2 | 0:1.1.1-1.el10_2 |
| Red Hat:hummingbird:1 | grafana13.1 | before 0:13.1.3-0.3.hum1 | 0:13.1.3-0.3.hum1 |
Same product
openjsf: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-84394fast-uri vulnerable to host confusion via an unclosed bracket in the URI authority30Monitor
- CVE-2026-84292fast-uri vulnerable to authority injection via an unvalidated port in serialize30Monitor
- CVE-2026-76172fast-uri vulnerable to host confusion via percent-encoded scheme normalization30Monitor
Published before and after this one in the same product
- ← EarlierCVE-2026-6321May 4, 2026 · fast-uri vulnerable to path traversal via percent-encoded dot segments30Monitor
- Later →CVE-2026-13676Jun 29, 2026 · fast-uri vulnerable to host confusion via failed IDN canonicalization30Monitor
- Later →CVE-2026-16221Jul 19, 2026 · fast-uri vulnerable to host confusion via literal backslash authority delimiter30Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| fast-uri fast-uri | 3.1.2 | Vendor (CNA) |
| debian:node-ajv | 8.20.0~ds+~cs6.1.3-1 · Debian:14 | Package registry (OSV) |
| npm:fast-uri | 2.4.1 | Package registry (OSV) |
| npm:fast-uri | 3.1.2 | Package registry (OSV) |
| red hat:automation-controller | 0:4.7.13-2.el9ap · Red Hat:ansible_automation_platform_developer:2.6::el9 | Package registry (OSV) |
| red hat:automation-controller-cli | 0:4.7.13-2.el9ap · Red Hat:ansible_automation_platform_developer:2.6::el9 | Package registry (OSV) |
| red hat:automation-controller-server | 0:4.7.13-2.el9ap · Red Hat:ansible_automation_platform:2.6::el9 | Package registry (OSV) |
| red hat:automation-controller-ui | 0:4.7.13-2.el9ap · Red Hat:ansible_automation_platform:2.6::el9 | Package registry (OSV) |
| red hat:automation-controller-venv-tower | 0:4.7.13-2.el9ap · Red Hat:ansible_automation_platform:2.6::el9 | Package registry (OSV) |
| red hat:automation-platform-ui | 0:2.6.10-1.el9ap · Red Hat:ansible_automation_platform:2.6::el9 | Package registry (OSV) |
| red hat:grafana13.1 | 0:13.1.3-0.3.hum1 · Red Hat:hummingbird:1 | Package registry (OSV) |
| red hat:python3.12-pyjwt | 0:2.13.0-1.el9ap · Red Hat:ansible_automation_platform:2.6::el9 | Package registry (OSV) |
| red hat:python3.12-pyjwt+crypto | 0:2.13.0-1.el9ap · Red Hat:ansible_automation_platform:2.6::el9 | Package registry (OSV) |
| red hat:python3.12-pysequoia | 0:0.1.34-1.el9ap · Red Hat:ansible_automation_platform:2.6::el9 | Package registry (OSV) |
| red hat:python3.12-pysequoia-debuginfo | 0:0.1.34-1.el9ap · Red Hat:ansible_automation_platform:2.6::el9 | Package registry (OSV) |
| red hat:python3.12-pysequoia-debugsource | 0:0.1.34-1.el9ap · Red Hat:ansible_automation_platform:2.6::el9 | Package registry (OSV) |
| red hat:python3.12-urllib3 | 0:2.7.0-1.el9ap · Red Hat:ansible_automation_platform_developer:2.6::el9 | Package registry (OSV) |
| red hat:rh-podman-desktop | 0:1.1.1-1.el10_2 · Red Hat:enterprise_linux:10.2 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
No history yet (it accumulates with the daily EPSS job).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
- Jvrreporter
- Matteo Collinaremediation developer
- KaKaremediation reviewer
- Ulises Gascónremediation developer
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2026-1367655 days apartfast-uri vulnerable to host confusion via failed IDN canonicalization30Monitor
- CVE-2026-1622175 days apartfast-uri vulnerable to host confusion via literal backslash authority delimiter30Monitor
- CVE-2026-1844687 days apartfast-uri vulnerable to host confusion via backslash authority introducer30Monitor
- CVE-2026-75931111 days apartfast-uri vulnerable to host confusion via skipped IDN canonicalization on scheme-relative references30Monitor
- CVE-2026-84394121 days apartfast-uri vulnerable to host confusion via an unclosed bracket in the URI authority30Monitor
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- high · data or configuration can be modified
- Availability
- none
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- High
- Availability impact
- None
Weakness class (CWE)
CWE-436 · Interpretation ConflictCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (19 more)Show less
- github.com/fastify/fast-uri/security/advisories/GHSA-v39h-62p7-jpjc
- access.redhat.com/errata/RHSA-2026:25271
- access.redhat.com/errata/RHSA-2026:25273
- access.redhat.com/errata/RHSA-2026:26225
- access.redhat.com/errata/RHSA-2026:26234
- access.redhat.com/errata/RHSA-2026:28571
- access.redhat.com/errata/RHSA-2026:29197
- access.redhat.com/errata/RHSA-2026:29795
- access.redhat.com/errata/RHSA-2026:29796
- access.redhat.com/errata/RHSA-2026:29800
- access.redhat.com/errata/RHSA-2026:29834
- access.redhat.com/errata/RHSA-2026:30076
- access.redhat.com/errata/RHSA-2026:33683
- access.redhat.com/errata/RHSA-2026:34160
- access.redhat.com/errata/RHSA-2026:34342
- access.redhat.com/errata/RHSA-2026:34374
- access.redhat.com/errata/RHSA-2026:34766
- access.redhat.com/errata/RHSA-2026:34770
- access.redhat.com/errata/RHSA-2026:36651
Vendor advisories and official records. Exploit/PoC links are deliberately left out.