Search/CVE-2026-21717
● CVE — Medium

CVE-2026-21717

VendornodejsProductnode.jsDiscoveredMar 30, 2026UpdatedAug 19, 2026

A flaw in V8's string hashing mechanism causes integer-like strings to be hashed to their numeric value, making hash collisions trivially predictable. By crafting a request that causes many such collisions in V8's internal string table, an attacker can significantly degrade performance of the Node.js process. The most common trigger is any endpoint that calls JSON.parse() on attacker-controlled input, as JSON parsing automatically internalizes short strings into the affected hash table. This vulnerability affects 20.x, 22.x, 24.x, and 25.x.

CVSS v3.1
5.9 MEDIUM
EPSS
0.27%
probability of exploitation in 30 days
CISA KEV
Not listed
no confirmed exploitation reported
News coverage
0
sources referencing this CVE
Related IOCs
0
seen in the same coverage
EPSS Trend
Aug 16, 2026 → Oct 28, 2026
▼ 0.01pp
0.28% → 0.27% over 3 tracked changes
CVSS v3.1 Detail
Attack VectorNETWORK
Attack ComplexityHIGH
Privileges RequiredNONE
User InteractionNONE
ScopeUNCHANGED
ConfidentialityNONE
IntegrityNONE
AvailabilityHIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Connections
2 relationships
Timeline
disclosure → media coverage
Mar 30, 2026
Disclosure — published as a CVE record. · last revised by NVD Aug 19, 2026
Public PoC (1)
Unverified third-party code — review before executing.