How severe is CVE-2026-34077?

CVE-2026-34077 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-2026-34077 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-34077?

CVE-2026-34077 primarily affects Shopify React-router. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-34077?

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-2026-34077 have an EU (EUVD) identifier?

Yes. CVE-2026-34077 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-33994.

When was CVE-2026-34077 published?

CVE-2026-34077 was published on 2026-06-02 and last updated on 2026-06-17.

CVE-2026-34077

CVE-2026-34077 is a high-severity vulnerability in Shopify React-router 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-770.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 0% (21st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-33994
Weakness: CWE-770
Affected product: Shopify React-router
Published: 2026-06-02
Last modified: 2026-06-17

Description

React Router is a router for React. In versions 7.7.0 through 7.13.1, when using React Router's unstable React Server Components (RSC) APIs, there is a potential client-side Cross-Site Scripting (XSS) vulnerability in the RSC redirect handling if redirects come from untrusted sources. This does not impact applications that are not using the unstable RSC APIs in React Router. This is patched in version 7.13.2.

Frequently asked questions

What is CVE-2026-34077?: React Router is a router for React. In versions 7.7.0 through 7.13.1, when using React Router's unstable React Server Components (RSC) APIs, there is a potential client-side Cross-Site Scripting (XSS) vulnerability in the RSC redirect handling if redirects come from untrusted sources. This does not impact applications that are not using the unstable RSC APIs in React Router. This is patched in version 7.13.2.
How severe is CVE-2026-34077?: CVE-2026-34077 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-2026-34077 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-34077?: CVE-2026-34077 primarily affects Shopify React-router. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-34077?: 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-2026-34077 have an EU (EUVD) identifier?: Yes. CVE-2026-34077 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-33994.
When was CVE-2026-34077 published?: CVE-2026-34077 was published on 2026-06-02 and last updated on 2026-06-17.

References

https://github.com/remix-run/react-router/security/advisories/GHSA-rxv8-25v2-qmq8

Affected products (2)

cpe:2.3:a:shopify:react-router:*:*:*:*:*:node.js:*:*
cpe:2.3:a:turbo-stream:turbo_stream:*:*:*:*:*:node.js:*:*

More vulnerabilities in Shopify React-router

CVE-2026-21884 — High (CVSS 8.2): React Router is a router for React. In @remix-run/react version prior to 2.17.3. and react-router 7.0.0 through 7.11.0,…
CVE-2026-42211 — High (CVSS 8.1): React Router is a router for React. In versions 7.0.0 through 7.14.1, when using Framework Mode, a combination of steps…
CVE-2026-33245 — High (CVSS 8.0): React Router is a router for React. In versions 7.7.0 through 7.13.1, when using React Router's unstable React Server…
CVE-2026-22029 — High (CVSS 8.0): React Router is a router for React. In @remix-run/router version prior to 1.23.2 and react-router 7.0.0 through 7.11.0,…
CVE-2025-59057 — High (CVSS 7.6): React Router is a router for React. In @remix-run/react versions 1.15.0 through 2.17.0. and react-router versions 7.0.0…
CVE-2026-42342 — High (CVSS 7.5): React Router is a router for React. In versions 7.0.0 through 7.14.x of react-router and versions 2.10.0 through 2.17.4…

All CVEs affecting Shopify React-router →

Other CWE-770 (Allocation of Resources Without Limits or Throttling) vulnerabilities

CVE-2026-31283 — Critical (CVSS 9.8): In Totara LMS v19.1.5 and before, the forgot password API does not implement rate limiting for the target email…
CVE-2020-37067 — Critical (CVSS 9.8): Filetto 1.0 FTP server contains a denial of service vulnerability in the FEAT command processing that allows attackers…
CVE-2021-47875 — Critical (CVSS 9.8): GeoGebra CAS Calculator 6.0.631.0 contains a denial of service vulnerability that allows attackers to crash the…
CVE-2025-11832 — Critical (CVSS 9.8): Allocation of Resources Without Limits or Throttling vulnerability in Azure Access Technology BLU-IC2, Azure Access…
CVE-2024-44241 — Critical (CVSS 9.8): The issue was addressed with improved bounds checks. This issue is fixed in iOS 18.1 and iPadOS 18.1, macOS Sequoia…
CVE-2022-3439 — Critical (CVSS 9.8): Allocation of Resources Without Limits or Throttling in GitHub repository ikus060/rdiffweb prior to 2.5.0.

Browse all CWE-770 (Allocation of Resources Without Limits or Throttling) vulnerabilities →