Vulnerability in zae-limiter (CVE-2026-27695)
Summary
Vulnerability in zae-limiter (CVE-2026-27695). Risk of unauthorized operations or information disclosure. Exploitable via TransactWriteItems. Mitigation: upgrade to 0.10.1 or later.
Original description
The description as published by the source.
Summary
All rate limit buckets for a single entity share the same DynamoDB partition key (namespace/ENTITY#{id}). A high-traffic entity can exceed DynamoDB's per-partition throughput limits (~1,000 WCU/sec), causing throttling that degrades service for that entity — and potentially co-located entities in the same partition.
Details
Each acquire() call performs a TransactWriteItems (or UpdateItem in speculative mode) against items sharing the same partition key. For cascade entities, this doubles to 2-4 writes per request (child + parent). At sustained rates above ~500 req/sec for a single entity, DynamoDB's adaptive capacity may not redistribute fast enough, causing ProvisionedThroughputExceededException.
The library has no built-in mitigation:
- No partition key sharding/salting
- No write coalescing or batching
- No client-side admission control before hitting DynamoDB
RateLimiterUnavailableis raised but the caller has already been delayed
Impact
- Availability: High-traffic entities experience elevated latency and rejected requests beyond what their rate limits specify
- Fairness: Other entities sharing the same DynamoDB partition may experience collateral throttling
- Multi-tenant risk: In a shared LLM proxy scenario, one tenant's burst traffic could degrade service for others
Reproduction
- Create an entity with high rate limits (e.g., 100,000 rpm)
- Send sustained traffic at 1,000+ req/sec to a single entity
- Observe Dy…
Source: OSV.dev (Open Source Vulnerabilities) NVD GitHub Advisory OSV
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-27695 has been found in zae-limiter.
Attackers can target a specific entry point like TransactWriteItems over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: upgrade zae-limiter to 0.10.1 or later.
If unsure, ask your IT team or search "zae-limiter CVE-2026-27695" on the vendor's site.
CVE-2026-27695 (zae-limiter) — CWE-770
Attack vector: remote (network-reachable) / no user interaction
Attack surface: TransactWriteItems / UpdateItem / ProvisionedThroughputExceededException / RateLimiterUnavailable
Patched: 0.10.1 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-770) exists in zae-limiter. Attackers reach the vulnerable code path via TransactWriteItems.
Check the vendor advisory for the affected versions of zae-limiter. Attack surface: TransactWriteItems / UpdateItem / ProvisionedThroughputExceededException / RateLimiterUnavailable.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 0.10.1.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'zae-limiter' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'zae-limiter' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
zae-limiterを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade zae-limiter to 0.10.1ステージング環境で 0.10.1 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory nvd.nist.gov
- package github.com
- web github.com
- web github.com
- web github.com