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NVD / CVE Program· CNA hackerone

CVE-2026-21713: A flaw in Node.js HMAC verification uses a non-constant-time comparison when validating user-provided signatures, potentially leaking timing

Noroxi assessment

Priority: Monitor (action score 23/100)

  • 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: 0.36% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. Special conditions such as timing or configuration are required.
  • 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 HMAC verification uses a non-constant-time comparison when validating user-provided signatures, potentially leaking timing information proportional to the number of matching bytes. Under certain threat models where high-resolution timing measurements are possible, this behavior could be exploited as a timing oracle to infer HMAC values. Node.js already provides timing-safe comparison primitives used elsewhere in the codebase, indicating this is an oversight rather than an intentional design decision. This vulnerability affects **20.x, 22.x, 24.x, and 25.x**.

MediumCVSS 5.9 · v3.0—No exploit Fix available
Published
Mar 30, 2026
Updated
Aug 19, 2026
EPSS
0.3% · 30th percentile

Report tools

JSON

Action score

23

Monitor

Low priority for now.

CVSS
23 / 40 · 5.9 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.3%

CISA SSVC decision

Exploitation
none
Automatable
yes
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · hackerone
5.9
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.

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  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

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  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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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.

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Affected 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.

VendorProduct
nodejsnode.js

Using node.js? Add it to your stack and be the first to know about CVEs like this one. (Node.js)

Watch new CVEs for node.js

When you'll hear from us

  • when a new CVE affecting this product is published
  • when a record in your stack enters KEV or gets exploit code

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  • Stack alerts: add the products and versions you run, get the new CVEs that affect them
  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools (3 a day without an account), an API key and MCP
  • All your scans in one panel: findings, what changed in the last scan, a report per domain or per client (PDF, share link)
All free tools

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Free account, no card. Unfollow any time.

Don't want an account? Get "Exploited this week" by email every Monday

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.

EcosystemPackageAffected rangeFix
AlmaLinux:10nodejs24-docsbefore 1:24.14.1-2.el10_11:24.14.1-2.el10_1
AlmaLinux:10nodejs24-npmbefore 1:11.11.0-1.24.14.1.2.el10_11:11.11.0-1.24.14.1.2.el10_1
AlmaLinux:8nodejsbefore 1:24.14.1-2.module_el8.10.0+4160+4819ac421:24.14.1-2.module_el8.10.0+4160+4819ac42
AlmaLinux:8nodejs-develbefore 1:24.14.1-2.module_el8.10.0+4160+4819ac421:24.14.1-2.module_el8.10.0+4160+4819ac42
AlmaLinux:8nodejs-docsbefore 1:24.14.1-2.module_el8.10.0+4160+4819ac421:24.14.1-2.module_el8.10.0+4160+4819ac42
AlmaLinux:8nodejs-full-i18nbefore 1:24.14.1-2.module_el8.10.0+4160+4819ac421:24.14.1-2.module_el8.10.0+4160+4819ac42
AlmaLinux:8nodejs-libsbefore 1:24.14.1-2.module_el8.10.0+4160+4819ac421:24.14.1-2.module_el8.10.0+4160+4819ac42
AlmaLinux:8nodejs-nodemonbefore 3.0.3-1.module_el8.10.0+4061+f8ceeab93.0.3-1.module_el8.10.0+4061+f8ceeab9
AlmaLinux:8nodejs-packagingbefore 2021.06-6.module_el8.10.0+4086+70facd4a2021.06-6.module_el8.10.0+4086+70facd4a
AlmaLinux:8nodejs-packaging-bundlerbefore 2021.06-6.module_el8.10.0+4086+70facd4a2021.06-6.module_el8.10.0+4086+70facd4a
AlmaLinux:8npmbefore 1:11.11.0-1.24.14.1.2.module_el8.10.0+4160+4819ac421:11.11.0-1.24.14.1.2.module_el8.10.0+4160+4819ac42
AlmaLinux:8v8-13.6-develbefore 3:13.6.233.17-1.24.14.1.2.module_el8.10.0+4160+4819ac423:13.6.233.17-1.24.14.1.2.module_el8.10.0+4160+4819ac42
AlmaLinux:9nodejsbefore 1:24.14.1-2.module_el9.7.0+222+ef1c61e11:24.14.1-2.module_el9.7.0+222+ef1c61e1
AlmaLinux:9nodejs-develbefore 1:24.14.1-2.module_el9.7.0+222+ef1c61e11:24.14.1-2.module_el9.7.0+222+ef1c61e1
AlmaLinux:9nodejs-docsbefore 1:24.14.1-2.module_el9.7.0+222+ef1c61e11:24.14.1-2.module_el9.7.0+222+ef1c61e1
AlmaLinux:9nodejs-full-i18nbefore 1:24.14.1-2.module_el9.7.0+222+ef1c61e11:24.14.1-2.module_el9.7.0+222+ef1c61e1
AlmaLinux:9nodejs-libsbefore 1:24.14.1-2.module_el9.7.0+222+ef1c61e11:24.14.1-2.module_el9.7.0+222+ef1c61e1
AlmaLinux:9nodejs-nodemonbefore 3.0.3-3.module_el9.7.0+209+ecf6523e3.0.3-3.module_el9.7.0+209+ecf6523e
AlmaLinux:9nodejs-packagingbefore 2021.06-6.module_el9.7.0+209+ecf6523e2021.06-6.module_el9.7.0+209+ecf6523e
AlmaLinux:9nodejs-packaging-bundlerbefore 2021.06-6.module_el9.7.0+198+8bf605ba2021.06-6.module_el9.7.0+198+8bf605ba
AlmaLinux:9npmbefore 1:11.11.0-1.24.14.1.2.module_el9.7.0+222+ef1c61e11:11.11.0-1.24.14.1.2.module_el9.7.0+222+ef1c61e1
AlmaLinux:9v8-13.6-develbefore 3:13.6.233.17-1.24.14.1.2.module_el9.7.0+222+ef1c61e13:13.6.233.17-1.24.14.1.2.module_el9.7.0+222+ef1c61e1
Alpine:v3.21nodejsbefore 22.22.2-r022.22.2-r0
Alpine:v3.23nodejsbefore 24.14.1-r024.14.1-r0

+56

Same product

nodejs: all records

Other 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 malformed
    56Plan
  • 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 c
    50Plan

Published before and after this one in the same product

  • ← EarlierCVE-2026-21710Mar 30, 2026 · 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
    38Monitor
  • ← EarlierCVE-2026-21711Mar 30, 2026 · A flaw in Node.js Permission Model network enforcement leaves Unix Domain Socket (UDS) server operations without the required permission che
    21Monitor
  • Later →CVE-2026-21714Mar 30, 2026 · A memory leak occurs in Node.js HTTP/2 servers when a client sends WINDOW_UPDATE frames on stream 0 (connection-level) that cause the flow c
    21Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
nodejs node10.*Vendor (CNA)
nodejs node11.*Vendor (CNA)
nodejs node12.*Vendor (CNA)
nodejs node13.*Vendor (CNA)
nodejs node14.*Vendor (CNA)
nodejs node15.*Vendor (CNA)
nodejs node16.*Vendor (CNA)
nodejs node17.*Vendor (CNA)
nodejs node18.*Vendor (CNA)
nodejs node19.*Vendor (CNA)
nodejs node4.*Vendor (CNA)
nodejs node5.*Vendor (CNA)
nodejs node6.*Vendor (CNA)
nodejs node7.*Vendor (CNA)
nodejs node8.*Vendor (CNA)
nodejs node9.*Vendor (CNA)
azl3 nodejs 20.14.0-14 on Azure Linux 3.020.14.0-15 · CBL-Mariner ReleasesMicrosoft (MSRC)
azl3 nodejs24 24.13.0-3 on Azure Linux 3.024.14.1-1 · CBL-Mariner ReleasesMicrosoft (MSRC)
almalinux:nodejs1:24.14.1-2.module_el9.7.0+222+ef1c61e1 · AlmaLinux:9Package registry (OSV)
almalinux:nodejs-devel1:24.14.1-2.module_el9.7.0+222+ef1c61e1 · AlmaLinux:9Package registry (OSV)
almalinux:nodejs-docs1:24.14.1-2.module_el9.7.0+222+ef1c61e1 · AlmaLinux:9Package registry (OSV)
almalinux:nodejs-full-i18n1:24.14.1-2.module_el9.7.0+222+ef1c61e1 · AlmaLinux:9Package registry (OSV)
almalinux:nodejs-libs1:24.14.1-2.module_el9.7.0+222+ef1c61e1 · AlmaLinux:9Package registry (OSV)
almalinux:nodejs-nodemon3.0.3-3.module_el9.7.0+209+ecf6523e · AlmaLinux:9Package registry (OSV)
almalinux:nodejs-packaging2021.06-6.module_el9.7.0+209+ecf6523e · AlmaLinux:9Package registry (OSV)
almalinux:nodejs-packaging-bundler2021.06-6.module_el9.7.0+198+8bf605ba · AlmaLinux:9Package registry (OSV)
almalinux:nodejs24-docs1:24.14.1-2.el10_1 · AlmaLinux:10Package registry (OSV)
almalinux:nodejs24-npm1:11.11.0-1.24.14.1.2.el10_1 · AlmaLinux:10Package registry (OSV)
almalinux:npm1:11.11.0-1.24.14.1.2.module_el9.7.0+222+ef1c61e1 · AlmaLinux:9Package registry (OSV)
almalinux:v8-13.6-devel3:13.6.233.17-1.24.14.1.2.module_el9.7.0+222+ef1c61e1 · AlmaLinux:9Package registry (OSV)

+24

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 researchers

Finders, 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.
  • Special conditions such as timing or configuration are required.

If successful

Confidentiality
high · data can be read
Integrity
none
Availability
none
Attack vector
Network
Attack complexity
High
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
None
Availability impact
None

Weakness class (CWE)

CWE-208 · Observable Timing Discrepancy

CVSS vector

CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/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

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records