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NVD / CVE Program· CNA apache

CVE-2021-22160: Authentication with JWT allows use of “none”-algorithm

CriticalCVSS 9.8 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Plan (action score 55/100)

  • 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: 52.9% (FIRST EPSS); higher than 98.9% 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.
  • Fixed version: org.apache.pulsar:pulsar (Maven) 2.7.2.

Add it to your regular patch cycle. Upgrade to org.apache.pulsar:pulsar (Maven) 2.7.2 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

If Apache Pulsar is configured to authenticate clients using tokens based on JSON Web Tokens (JWT), the signature of the token is not validated if the algorithm of the presented token is set to "none". This allows an attacker to connect to Pulsar instances as any user (incl. admins).

Published
May 26, 2021
Updated
Jun 16, 2026
EPSS
52.9% · 98th percentile

Report tools

JSON

Action score

55

Plan

Add it to your regular patch cycle.

CVSS
39 / 40 · 9.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
16 / 30 · 52.9%

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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 you'll hear from us

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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
apachepulsar

Versions reported by the vendor

Affected version ranges reported by the assigning authority (apache). Independent of NVD's CPE analysis and usually ahead of it.

  • Apache Software Foundation Apache Pulsar

    • Apache Pulsar and later · before 2.7.1affected

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • apache pulsarbefore 2.7.1

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Mavenorg.apache.pulsar:pulsarbefore 2.7.22.7.2

Same product

apache: all records

Other highest-scoring records for the same primary product.

  • CVE-2024-27317Apache Pulsar: Pulsar Functions Worker's Archive Extraction Vulnerability Allows Unauthorized File Modification
    56Plan
  • CVE-2024-27135Apache Pulsar: Improper Input Validation in Pulsar Function Worker allows Remote Code Execution
    41Plan
  • CVE-2024-27894Apache Pulsar: Pulsar Functions Worker Allows Unauthorized File Access and Unauthorized HTTP/HTTPS Proxying
    36Monitor

Published before and after this one in the same product

  • Later →CVE-2021-41571Feb 1, 2022 · Pulsar Admin API allows access to data from other tenants using getMessageById API
    27Monitor
  • Later →CVE-2022-24280Sep 23, 2022 · Apache Pulsar Proxy target broker address isn't validated
    26Monitor
  • Later →CVE-2022-33681Sep 23, 2022 · Improper Hostname Verification in Java Client and Proxy can expose authentication data via MITM
    23Monitor

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
Maven:org.apache.pulsar:pulsar2.7.2Package 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.

Not on record for this CVE: EPSS history · patch commit or PR link · researcher credit · variant or chain candidate · public bounty 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
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-347 · Improper Verification of Cryptographic Signature

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvd-primary

Root cause

The verifier takes the algorithm to verify with from the token’s own header. Untrusted data ends up deciding its own verification rule.

The bug in code

The whole CWE-347 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

ts
const claims = jwt.verify(token, publicKey);

Fixed

ts
const claims = jwt.verify(token, publicKey, {  algorithms: ["RS256"],  issuer: "https://id.example.com",  audience: "portal",});

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

ATT&CK techniques

—

References

Show all references (7 more)

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

All records