CVE-2026-16221

highpriority · track · 0EPSS 0.004 · 38 %ileDEEUFRNLUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.44% (38th) EPSS
CVSS 7.5 · high
Is it mine?
40 products
Check your exposure
Who says so?
6 sources
cnnvd · enisa_euvd · cert_bund · ncsc_nl

EPSS · scored 2026-10-26

Impact: fast-uri versions from 2.3.1 through 4.1.0 (including the 3.x line up to 3.1.3 and the 2.x line up to 2.4.2) do not treat a literal backslash character (U+005C) as an authority delimiter. Node's native WHATWG URL parser, used by fetch, undici, and Node's http and https clients, normalizes the backslash to a forward slash for special schemes such as http, https, ws, wss, ftp, and file. As a result, the two parsers extract different hosts from the same input string. Applications that use fast-uri to enforce host-based policy such as allowlists, denylists, loopback or SSRF filtering, redirect validation, or outbound proxy routing before passing the same URL into Node's URL or fetch consumers can be steered to an unintended destination, including cloud metadata endpoints, loopback, or internal hosts. Patches: upgrade to fast-uri 4.1.1, 3.1.4, or 2.4.3. Workarounds: none.

01

cvss

Technical severity, 0–10. One row per scoring source.

7.5
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–7.5

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:Nsecondary · ENISA EU
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:Nsecondaryexploitability 3.9 · impact 3.6
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:Nsecondary · OSV
v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:Nsecondary · NCSC-NL NL
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-436USCWE-436USCWE-436US
04

affected products (40)

Products and version ranges known to be affected.

showing 20 of 40
05

advisories (5)

Vendor and ecosystem advisories describing this.

  • NCSC-2026-0325Kwetsbaarheden verholpen in Atlassian productenNL2026-08-24csaf · ncsc_nlNL

    Atlassian heeft kwetsbaarheden verholpen in diverse producten zoals Bamboo, Bitbucket, Confluence, Jira, Crowd en Fisheye. De kwetsbaarheden bevinden zich in diverse Third-Party producten waar eerder updates voor zijn verschenen. Atlassian heeft deze updates verwerkt in de eigen producten.

  • WID-SEC-W-2026-2923Atlassian Produkte (Bamboo, Bitbucket, Confluence, Crucible, Fisheye, und Jira): Mehrere SchwachstellenDeutsch2026-08-18csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in Atlassian Bamboo, Atlassian Bitbucket, Atlassian Confluence, Atlassian Crucible, Atlassian Fisheye und Atlassian Jira ausnutzen, um beliebigen Programmcode auszuführen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, um Dateien zu manipulieren, um einen Cross-Site Scripting Angriff durchzuführen, um einen SQL-Injection Angriff durchzuführen, und um Sicherheitsvorkehrungen zu umgehen.

  • WID-SEC-W-2026-3376Atlassian Bamboo, Bitbucket, Confluence, Fisheye/Crucible, Jira Software und Jira Service Management: Mehrere SchwachstellenDeutsch2026-09-15csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in Atlassian Bamboo, Bitbucket, Confluence, Fisheye/Crucible, Jira Software und Jira Service Management ausnutzen, um beliebigen Programmcode auszuführen, Sicherheitsmaßnahmen zu umgehen, serverseitige Request-Forgery-Angriffe (SSRF) durchzuführen, Cross-Site-Scripting-Angriffe zu starten, sensible Informationen offenzulegen, Daten zu manipulieren oder Denial-of-Service-Zustände herbeizuführen.

  • GHSA-v2hh-gcrm-f6hxfast-uri vulnerable to host confusion via literal backslash authority delimiter2026-07-21ghsa · osvUS

    ### Impact `fast-uri` v4.1.0 and earlier do not treat a literal backslash (U+005C) as an authority delimiter. Node's native WHATWG `URL` (used by `fetch()`, `undici`, and Node's `http`/`https` clients) normalizes `\` to `/` for special schemes (`http`, `https`, `ws`, `wss`, `ftp`, `file`), so the two parsers extract different hosts from the same input string. For example, `http://evil.com\@allowed.com` is treated by `fast-uri` as host `allowed.com` with userinfo `evil.com\`, while Node's WHATWG URL parser and `fetch()` see host `evil.com` with path `/@allowed.com`. Applications that use `fast-uri` to enforce host-based policy (allowlists, denylists, loopback/SSRF filtering, redirect validation, outbound proxy routing) before passing the same URL into Node's URL or `fetch()` consumers see a policy/use desync and can be steered to an unintended destination, including cloud metadata endpoints, loopback, or internal hosts. ### Patches Upgrade to `fast-uri` v4.1.1, v3.1.4, or v2.4.3. ### Workarounds None. Upgrade to the patched version.

  • CERTFR-2026-AVI-1336Multiples vulnérabilités dans les produits IBMFrançais2026-10-16vendor · certfrFR
06

also known as (3)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

cnnvdenisa_euvdcert_bundncsc_nlosvcertfrNVDCVE.orgMITRE
published 2026-07-19modified 2026-08-05
08

references (6)

External citations — patches, advisories, analysis.

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