CVE-2026-21710: A flaw in Node.js HTTP request handling causes an uncaught `TypeError` when a request is received with a header named `__proto__` and the ap
Noroxi assessment
Priority: Monitor (action score 38/100)
- Public proof-of-concept code exists (GitHub); there is no record of exploitation in the wild.
- Probability of exploitation in the next 30 days: 25.4% (FIRST EPSS); higher than 97.9% of all records.
- 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: nodejs node 10.*, 11.*, 12.*; azl3 nodejs 20.14.0-14 on Azure Linux 3.0 20.14.0-15; azl3 nodejs24 24.13.0-3 on Azure Linux 3.0 24.14.1-1.
Low priority for now. Upgrade to nodejs node 10.*, 11.*, 12.*; azl3 nodejs 20.14.0-14 on Azure Linux 3.0 20.14.0-15; azl3 nodejs24 24.13.0-3 on Azure Linux 3.0 24.14.1-1 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
A flaw in Node.js HTTP request handling causes an uncaught `TypeError` when a request is received with a header named `__proto__` and the application accesses `req.headersDistinct`. When this occurs, `dest["__proto__"]` resolves to `Object.prototype` rather than `undefined`, causing `.push()` to be called on a non-array. This exception is thrown synchronously inside a property getter and cannot be intercepted by `error` event listeners, meaning it cannot be handled without wrapping every `req.headersDistinct` access in a `try/catch`. * This vulnerability affects all Node.js HTTP servers on **20.x, 22.x, 24.x, and v25.x**
- BDU:2026-04840
- ALSA-2026:7080
- ALSA-2026:7123
- ALSA-2026:7350
- ALSA-2026:7670
- ALSA-2026:7675
- ALSA-2026:7896
- ALSA-2026:8339
- DSA-6183-1
- openSUSE-SU-2026:10504-1
- openSUSE-SU-2026:11110-1
- openSUSE-SU-2026:20519-1
- openSUSE-SU-2026:21058-1
- RHSA-2026:7080
- RHSA-2026:7123
- RHSA-2026:7302
- RHSA-2026:7310
- RHSA-2026:7350
- RHSA-2026:7670
- RHSA-2026:7675
- Published
- Mar 30, 2026
- Updated
- Aug 19, 2026
- EPSS
- 25.4% · 97th percentile
- CWE
- CWE-770
Report tools
Action score
38
Monitor
Low priority for now.
- CVSS
- 30 / 40 · 7.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 8 / 30 · 25.4%
CISA SSVC decision
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · hackerone
- 7.5
- NVD has not scored this yet; the score shown is the CNA’s.
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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
- Proof of concept exists, no weaponized module
- 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 |
|---|---|---|
| nodejs | node.js | cpe:2.3:a:nodejs:node.js |
| redhat | enterprise linux | cpe:2.3:o:redhat:enterprise_linux |
| redhat | enterprise linux eus | cpe:2.3:o:redhat:enterprise_linux_eus |
Using node.js? Add it to your stack and be the first to know about CVEs like this one. (Node.js)
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- nodejs node.jsup to 20.20.1 inclusive
- nodejs node.js22.0.0 and later · up to 22.22.1 inclusive
- nodejs node.js24.0.0 and later · up to 24.14.0 inclusive
- nodejs node.js25.0.0 and later · up to 25.8.1 inclusive
Versions reported by the vendor
Affected version ranges reported by the assigning authority (hackerone). Independent of NVD's CPE analysis and usually ahead of it.
nodejs node
- 20.20.1 and later · up to and including 20.20.1affected · semver
- 22.22.1 and later · up to and including 22.22.1affected · semver
- 24.14.0 and later · up to and including 24.14.0affected · semver
- 25.8.1 and later · up to and including 25.8.1affected · semver
- 4.0 and later · before 4.*affected · semver
- 5.0 and later · before 5.*affected · semver
- 6.0 and later · before 6.*affected · semver
- 7.0 and later · before 7.*affected · semver
- 8.0 and later · before 8.*affected · semver
- 9.0 and later · before 9.*affected · semver
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| AlmaLinux:10 | nodejs-docs | before 1:22.22.2-1.el10_1 | 1:22.22.2-1.el10_1 |
| AlmaLinux:10 | nodejs24-docs | before 1:24.14.1-2.el10_1 | 1:24.14.1-2.el10_1 |
| AlmaLinux:10 | nodejs24-npm | before 1:11.11.0-1.24.14.1.2.el10_1 | 1:11.11.0-1.24.14.1.2.el10_1 |
| AlmaLinux:8 | nodejs | before 1:24.14.1-2.module_el8.10.0+4160+4819ac42 | 1:24.14.1-2.module_el8.10.0+4160+4819ac42 |
| AlmaLinux:8 | nodejs | before 1:20.20.2-1.module_el8.10.0+4165+3f200bda | 1:20.20.2-1.module_el8.10.0+4165+3f200bda |
| AlmaLinux:8 | nodejs | before 1:22.22.2-1.module_el8.10.0+4158+e796f37f | 1:22.22.2-1.module_el8.10.0+4158+e796f37f |
| AlmaLinux:8 | nodejs-devel | before 1:20.20.2-1.module_el8.10.0+4165+3f200bda | 1:20.20.2-1.module_el8.10.0+4165+3f200bda |
| AlmaLinux:8 | nodejs-devel | before 1:22.22.2-1.module_el8.10.0+4158+e796f37f | 1:22.22.2-1.module_el8.10.0+4158+e796f37f |
| AlmaLinux:8 | nodejs-devel | before 1:24.14.1-2.module_el8.10.0+4160+4819ac42 | 1:24.14.1-2.module_el8.10.0+4160+4819ac42 |
| AlmaLinux:8 | nodejs-docs | before 1:24.14.1-2.module_el8.10.0+4160+4819ac42 | 1:24.14.1-2.module_el8.10.0+4160+4819ac42 |
| AlmaLinux:8 | nodejs-docs | before 1:22.22.2-1.module_el8.10.0+4158+e796f37f | 1:22.22.2-1.module_el8.10.0+4158+e796f37f |
| AlmaLinux:8 | nodejs-docs | before 1:20.20.2-1.module_el8.10.0+4165+3f200bda | 1:20.20.2-1.module_el8.10.0+4165+3f200bda |
| AlmaLinux:8 | nodejs-full-i18n | before 1:20.20.2-1.module_el8.10.0+4165+3f200bda | 1:20.20.2-1.module_el8.10.0+4165+3f200bda |
| AlmaLinux:8 | nodejs-full-i18n | before 1:22.22.2-1.module_el8.10.0+4158+e796f37f | 1:22.22.2-1.module_el8.10.0+4158+e796f37f |
| AlmaLinux:8 | nodejs-full-i18n | before 1:24.14.1-2.module_el8.10.0+4160+4819ac42 | 1:24.14.1-2.module_el8.10.0+4160+4819ac42 |
| AlmaLinux:8 | nodejs-libs | before 1:22.22.2-1.module_el8.10.0+4158+e796f37f | 1:22.22.2-1.module_el8.10.0+4158+e796f37f |
| AlmaLinux:8 | nodejs-libs | before 1:24.14.1-2.module_el8.10.0+4160+4819ac42 | 1:24.14.1-2.module_el8.10.0+4160+4819ac42 |
| AlmaLinux:8 | nodejs-nodemon | before 3.0.1-1.module_el8.10.0+3982+85c136aa | 3.0.1-1.module_el8.10.0+3982+85c136aa |
| AlmaLinux:8 | nodejs-nodemon | before 3.0.1-1.module_el8.10.0+4006+3c416519 | 3.0.1-1.module_el8.10.0+4006+3c416519 |
| AlmaLinux:8 | nodejs-nodemon | before 3.0.3-1.module_el8.10.0+4061+f8ceeab9 | 3.0.3-1.module_el8.10.0+4061+f8ceeab9 |
| AlmaLinux:8 | nodejs-packaging | before 2021.06-6.module_el8.10.0+4165+3f200bda | 2021.06-6.module_el8.10.0+4165+3f200bda |
| AlmaLinux:8 | nodejs-packaging | before 2021.06-6.module_el8.10.0+4158+e796f37f | 2021.06-6.module_el8.10.0+4158+e796f37f |
| AlmaLinux:8 | nodejs-packaging | before 2021.06-6.module_el8.10.0+4086+70facd4a | 2021.06-6.module_el8.10.0+4086+70facd4a |
| AlmaLinux:8 | nodejs-packaging-bundler | before 2021.06-6.module_el8.10.0+4158+e796f37f | 2021.06-6.module_el8.10.0+4158+e796f37f |
+96
Same product
nodejs: all recordsOther highest-scoring records for the same primary product.
- CVE-2019-15605HTTP request smuggling in Node.js 10, 12, and 13 causes malicious payload delivery when transfer-encoding is malformed56Plan
- CVE-2021-22883Node.js before 10.24.0, 12.21.0, 14.16.0, and 15.10.0 is vulnerable to a denial of service attack when too many connection attempts with an 53Plan
- CVE-2021-22930Node.js before 16.6.0, 14.17.4, and 12.22.4 is vulnerable to a use after free attack where an attacker might be able to exploit the memory c50Plan
Published before and after this one in the same product
- ← EarlierCVE-2026-21637Jan 20, 2026 · A flaw in Node.js TLS error handling allows remote attackers to crash or exhaust resources of a TLS server when `pskCallback` or `ALPNCallba30Monitor
- ← EarlierCVE-2026-21712Mar 30, 2026 · A flaw in Node.js URL processing causes an assertion failure in native code when `url.format()` is called with a malformed internationalized26Monitor
- Later →CVE-2026-21711Mar 30, 2026 · A flaw in Node.js Permission Model network enforcement leaves Unix Domain Socket (UDS) server operations without the required permission che21Monitor
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 |
|---|---|---|
| nodejs node | 10.* | Vendor (CNA) |
| nodejs node | 11.* | Vendor (CNA) |
| nodejs node | 12.* | Vendor (CNA) |
| nodejs node | 13.* | Vendor (CNA) |
| nodejs node | 14.* | Vendor (CNA) |
| nodejs node | 15.* | Vendor (CNA) |
| nodejs node | 16.* | Vendor (CNA) |
| nodejs node | 17.* | Vendor (CNA) |
| nodejs node | 18.* | Vendor (CNA) |
| nodejs node | 19.* | Vendor (CNA) |
| nodejs node | 4.* | Vendor (CNA) |
| nodejs node | 5.* | Vendor (CNA) |
| nodejs node | 6.* | Vendor (CNA) |
| nodejs node | 7.* | Vendor (CNA) |
| nodejs node | 8.* | Vendor (CNA) |
| nodejs node | 9.* | Vendor (CNA) |
| azl3 nodejs 20.14.0-14 on Azure Linux 3.0 | 20.14.0-15 · CBL-Mariner Releases | Microsoft (MSRC) |
| azl3 nodejs24 24.13.0-3 on Azure Linux 3.0 | 24.14.1-1 · CBL-Mariner Releases | Microsoft (MSRC) |
| cbl2 nodejs18 18.20.3-12 on CBL-Mariner 2.0 | Release Notes | Microsoft (MSRC) |
| Microsoft Visual Studio 2019 version 16.11 (includes 16.0 - 16.10) | 16.11.59 | Microsoft (MSRC) |
| Microsoft Visual Studio 2022 version 17.14 | 17.14.38 | Microsoft (MSRC) |
| almalinux:nodejs | 1:22.22.2-1.module_el8.10.0+4158+e796f37f · AlmaLinux:8 | Package registry (OSV) |
| almalinux:nodejs-devel | 1:22.22.2-1.module_el8.10.0+4158+e796f37f · AlmaLinux:8 | Package registry (OSV) |
| almalinux:nodejs-docs | 1:22.22.2-1.el10_1 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:nodejs-full-i18n | 1:22.22.2-1.module_el8.10.0+4158+e796f37f · AlmaLinux:8 | Package registry (OSV) |
| almalinux:nodejs-libs | 1:22.22.2-1.module_el8.10.0+4158+e796f37f · AlmaLinux:8 | Package registry (OSV) |
| almalinux:nodejs-nodemon | 3.0.1-1.module_el8.10.0+4006+3c416519 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:nodejs-packaging | 2021.06-6.module_el8.10.0+4158+e796f37f · AlmaLinux:8 | Package registry (OSV) |
| almalinux:nodejs-packaging-bundler | 2021.06-6.module_el8.10.0+4158+e796f37f · AlmaLinux:8 | Package registry (OSV) |
| almalinux:nodejs24-docs | 1:24.14.1-2.el10_1 · AlmaLinux:10 | Package registry (OSV) |
+29
Exploit status
Proof of concept available
A public proof of concept or detection signature exists. Exploit knowledge is out there; don't delay patching.
Evidence
- Proof-of-concept repository on GitHub ×1
Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.
| Source | Kind | Date |
|---|---|---|
| Proof-of-concept repository on GitHub | stars:0 | 2026-04-01 |
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.
- Published
- First PoC+1 d
- TodayNov 8, 2026+223 d
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
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.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
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
The product’s vendor appears in a public program. Matched by name; verify the scope text in the program.
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
- none
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- High
Weakness class (CWE)
CWE-770 · Allocation of Resources Without Limits or ThrottlingCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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.
Attack patterns (CAPEC)
- FloodingCAPEC-125likelihood: High · Medium
- Excessive AllocationCAPEC-130likelihood: Medium · Medium
- XML Ping of the DeathCAPEC-147likelihood: Low · Medium
- Exponential Data ExpansionCAPEC-197likelihood: High · Medium
- Serialized Data Parameter BlowupCAPEC-229likelihood: High · High
- Serialized Data with Nested PayloadsCAPEC-230likelihood: Medium · High
- Oversized Serialized Data PayloadsCAPEC-231likelihood: Medium · High
- HTTP DoSCAPEC-469Low
ATT&CK techniques
- Network Denial of Service:Direct Network FloodT1498.001
- Network Denial of Service:Reflection AmplificationT1498.002
- Endpoint Denial of ServiceT1499
- Endpoint Denial of Service: OS Exhaustion FloodT1499.001
- Endpoint Denial of Service:Service Exhaustion FloodT1499.002
- Endpoint Denial of Service:Application Exhaustion FloodT1499.003
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (15 more)Show less
- access.redhat.com/errata/RHSA-2026:7080
- access.redhat.com/errata/RHSA-2026:7123
- access.redhat.com/errata/RHSA-2026:7302
- access.redhat.com/errata/RHSA-2026:7310
- access.redhat.com/errata/RHSA-2026:7350
- access.redhat.com/errata/RHSA-2026:7670
- access.redhat.com/errata/RHSA-2026:7675
- access.redhat.com/errata/RHSA-2026:7896
- access.redhat.com/errata/RHSA-2026:7983
- access.redhat.com/errata/RHSA-2026:8339
- access.redhat.com/errata/RHSA-2026:9711
- access.redhat.com/errata/RHSA-2026:9874
- access.redhat.com/security/cve/CVE-2026-21710
- bugzilla.redhat.com/show_bug.cgi?id=2453151
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-21710.json
Vendor advisories and official records. Exploit/PoC links are deliberately left out.