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NVD / CVE Program· CNA GitHub_M

CVE-2025-49826: Next.js DoS vulnerability via cache poisoning

HighCVSS 7.5 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 30/100)

  • 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: 1.1% (FIRST EPSS); higher than 66.9% 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.
  • According to CISA the attack is automatable: targets can be found by mass scanning.
  • Fixed version: vercel next.js 15.1.8.

Low priority for now. Upgrade to vercel next.js 15.1.8 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

Next.js is a React framework for building full-stack web applications. From versions 15.0.4-canary.51 to before 15.1.8, a cache poisoning bug leading to a Denial of Service (DoS) condition was found in Next.js. This issue does not impact customers hosted on Vercel. Under certain conditions, this issue may allow a HTTP 204 response to be cached for static pages, leading to the 204 response being served to all users attempting to access the page. This issue has been addressed in version 15.1.8.

Published
Jul 3, 2025
Updated
Jun 17, 2026
EPSS
1.1% · 66th percentile

Report tools

JSON

Action score

30

Monitor

Low priority for now.

CVSS
30 / 40 · 7.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 1.1%

CISA SSVC decision

Exploitation
none
Automatable
yes
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · GitHub_M
7.5
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.

Get told when this record changes

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

If any of these changes, we'll tell you in the daily email digest.

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When you'll hear from us

  • when it enters CISA KEV
  • 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
vercelnext.js

Is the Next.js on your site affected?

The free JavaScript library scanner reads the Next.js version from the files your site loads, matches this record and other known vulnerabilities, and gives the safe version on the same branch. If the version can't be read, it says so. No account needed.

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Versions reported by the vendor

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

  • vercel next.js

    • >= 15.0.4-canary.51, < 15.1.8affected

Affected versions

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

  • vercel next.jsafter 15.0.4 · before 15.1.8
  • vercel next.js15.0.4

Package-level exposure

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

EcosystemPackageAffected rangeFix
npmnextfrom 15.0.4-canary.51 · before 15.1.815.1.8

Same product

vercel: all records

Other highest-scoring records for the same primary product.

  • CVE-2025-29927Authorization Bypass in Next.js Middleware
    66This week
  • CVE-2026-75604Next.js: Unauthenticated Remote Code Execution on windows-hosted servers
    60This week
  • CVE-2024-46982Cache Poisoning in next.js
    48Plan

Published before and after this one in the same product

  • ← EarlierCVE-2025-48068May 30, 2025 · Information exposure in Next.js dev server due to lack of origin verification
    9Monitor
  • ← EarlierCVE-2025-49005Jul 3, 2025 · Next.js cache poisoning due to omission of Vary header
    14Monitor
  • Later →CVE-2025-55173Aug 29, 2025 · Next.js Content Injection Vulnerability for Image Optimization
    17Monitor

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
vercel next.js15.1.8 · descriptionVendor (CNA)
npm:next15.1.8Package 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.

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2024-34350415 days apartNext.js Vulnerable to HTTP Request Smuggling
    30Monitor
  • CVE-2026-29057257 days apartNext.js: HTTP request smuggling in rewrites
    25Monitor
  • CVE-2025-490050 days apartNext.js cache poisoning due to omission of Vary header
    14Monitor

Bug bounty scope

The product’s vendor appears in a public program. Matched by name; verify the scope text in the program.

Not on record for this CVE: EPSS history · researcher credit.

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
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

CWE-444 · Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

CVSS vector

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

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.

ATT&CK techniques

—

References

Show all references (3 more)

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

All records