How severe is CVE-2025-55173?

CVE-2025-55173 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2025-55173 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (40th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-55173?

CVE-2025-55173 affects Vercel Next.js. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-55173?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2025-55173 have an EU (EUVD) identifier?

Yes. CVE-2025-55173 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-26244.

When was CVE-2025-55173 published?

CVE-2025-55173 was published on 2025-08-29 and last updated on 2026-06-17.

CVE-2025-55173

CVE-2025-55173 is a medium-severity vulnerability in Vercel Next.js with a CVSS 3.x base score of 4.3. 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-20.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
EPSS exploit prediction: 1% (40th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-26244
Weakness: CWE-20
Affected product: Vercel Next.js
Published: 2025-08-29
Last modified: 2026-06-17

Description

Next.js is a React framework for building full-stack web applications. In versions before 14.2.31 and from 15.0.0 to before 15.4.5, Next.js Image Optimization is vulnerable to content injection. The issue allowed attacker-controlled external image sources to trigger file downloads with arbitrary content and filenames under specific configurations. This behavior could be abused for phishing or malicious file delivery. This vulnerability has been fixed in Next.js versions 14.2.31 and 15.4.5.

Frequently asked questions

What is CVE-2025-55173?: Next.js is a React framework for building full-stack web applications. In versions before 14.2.31 and from 15.0.0 to before 15.4.5, Next.js Image Optimization is vulnerable to content injection. The issue allowed attacker-controlled external image sources to trigger file downloads with arbitrary content and filenames under specific configurations. This behavior could be abused for phishing or malicious file delivery. This vulnerability has been fixed in Next.js versions 14.2.31 and 15.4.5.
How severe is CVE-2025-55173?: CVE-2025-55173 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2025-55173 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (40th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-55173?: CVE-2025-55173 affects Vercel Next.js. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-55173?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-55173 have an EU (EUVD) identifier?: Yes. CVE-2025-55173 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-26244.
When was CVE-2025-55173 published?: CVE-2025-55173 was published on 2025-08-29 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:vercel:next.js:*:*:*:*:*:node.js:*:*

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