CVSS 3.1
3.7 lowCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:LCVE-2026-126204 express-rate-limit skipFailedRequests / skipSuccessfulRequests: with the default MemoryStore, a request from an earlier window is still un-counted from the current window
Low (3.7) in express-rate-limit express-rate-limit. EPSS 0.3% estimated probability of exploitation activity in the next 30 days.
On this page
express-rate-limit is a basic rate-limiting middleware for Express. From 8.6.0 until 8.7.2, the built-in MemoryStore returns a Client whose mutable resetTime object is retained by middleware using skipFailedRequests or skipSuccessfulRequests. When a later request resets the client window, MemoryStore.resetClient mutates that same Date, so an earlier request that finishes or disconnects after the reset can pass the stale-window guard and decrement the current window's count. A client able to keep requests in flight across the boundary can obtain a bounded extra burst of up to one additional configured limit in the new window; the behavior does not increase the sustained rate. Stores that return a fresh Date are not affected. This issue is fixed in version 8.7.2.
Severity
- EPSS
- 0.3% estimated probability of exploitation activity in the next 30 days; 20th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CISA's assessment (SSVC)
- Exploitation: none · Automatable: no · Technical impact: partial, assessed 2026-11-13. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
- CWE
- CWE-682 Incorrect Calculation
- Published
- Modified
- Assigned by
- GitHub_M (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
Ask an AI about this CVE
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Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| express-rate-limit | >= 8.6.0, < 8.7.2 |
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Ubuntu | 26.10 | node-express-rate-limit | no fix listed | UBUNTU-CVE-2026-126204 |
From the distributions' data via OSV.dev: Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Ubuntu.
Attack patterns (CAPEC)
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.
References
- https://github.com/express-rate-limit/express-rate-limit/commit/da5b115b97dd903076d37b19437fbd71445e150b
- https://github.com/express-rate-limit/express-rate-limit/pull/707
- https://github.com/express-rate-limit/express-rate-limit/releases/tag/v8.7.2
- https://github.com/express-rate-limit/express-rate-limit/security/advisories/GHSA-j3cq-92fq-qg5f