How severe is CVE-2026-34573?

CVE-2026-34573 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-34573 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-34573?

CVE-2026-34573 primarily affects Parseplatform Parse-server. In total, 12 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-34573?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-34573 have an EU (EUVD) identifier?

Yes. CVE-2026-34573 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17500.

When was CVE-2026-34573 published?

CVE-2026-34573 was published on 2026-03-31 and last updated on 2026-06-17.

CVE-2026-34573

CVE-2026-34573 is a high-severity vulnerability in Parseplatform Parse-server with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-407.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v4: 8.2
EPSS exploit prediction: 0% (37th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-17500
Weakness: CWE-407
Affected product: Parseplatform Parse-server
Published: 2026-03-31
Last modified: 2026-06-17

Description

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.68 and 9.7.0-alpha.12, the GraphQL query complexity validator can be exploited to cause a denial-of-service by sending a crafted query with binary fan-out fragment spreads. A single unauthenticated request can block the Node.js event loop for seconds, denying service to all concurrent users. This only affects deployments that have enabled the requestComplexity.graphQLDepth or requestComplexity.graphQLFields configuration options. This issue has been patched in versions 8.6.68 and 9.7.0-alpha.12.

Frequently asked questions

What is CVE-2026-34573?: Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.68 and 9.7.0-alpha.12, the GraphQL query complexity validator can be exploited to cause a denial-of-service by sending a crafted query with binary fan-out fragment spreads. A single unauthenticated request can block the Node.js event loop for seconds, denying service to all concurrent users. This only affects deployments that have enabled the requestComplexity.graphQLDepth or requestComplexity.graphQLFields configuration options. This issue has been patched in versions 8.6.68 and 9.7.0-alpha.12.
How severe is CVE-2026-34573?: CVE-2026-34573 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-34573 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-34573?: CVE-2026-34573 primarily affects Parseplatform Parse-server. In total, 12 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-34573?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-34573 have an EU (EUVD) identifier?: Yes. CVE-2026-34573 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17500.
When was CVE-2026-34573 published?: CVE-2026-34573 was published on 2026-03-31 and last updated on 2026-06-17.

References

Affected products (12)

cpe:2.3:a:parseplatform:parse-server:*:*:*:*:*:node.js:*:*
cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha1:*:*:*:node.js:*:*
cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha10:*:*:*:node.js:*:*
cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha11:*:*:*:node.js:*:*
cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha2:*:*:*:node.js:*:*
cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha3:*:*:*:node.js:*:*
cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha4:*:*:*:node.js:*:*
cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha5:*:*:*:node.js:*:*
cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha6:*:*:*:node.js:*:*
cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha7:*:*:*:node.js:*:*
cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha8:*:*:*:node.js:*:*
cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha9:*:*:*:node.js:*:*

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