Vulnerability in Abacus SSE Implementation (CVE-2025-27421)
Summary
Vulnerability in Abacus SSE Implementation (CVE-2025-27421). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 1.4.0 or later.
Original description
The description as published by the source.
Abacus is a highly scalable and stateless counting API. A critical goroutine leak vulnerability has been identified in the Abacus server's Server-Sent Events (SSE) implementation. The issue occurs when clients disconnect from the /stream endpoint, as the server fails to properly clean up resources and terminate associated goroutines. This leads to resource exhaustion where the server continues running but eventually stops accepting new SSE connections while maintaining high memory usage. The vulnerability specifically involves improper channel cleanup in the event handling mechanism, causing goroutines to remain blocked indefinitely. This vulnerability is fixed in 1.4.0.
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-2025-27421 has been found in Abacus SSE Implementation.
Risk of unauthorized operations or information disclosure.
What to do: upgrade Abacus SSE Implementation to 1.4.0 or later.
If unsure, ask your IT team or search "Abacus SSE Implementation CVE-2025-27421" on the vendor's site.
CVE-2025-27421 (Abacus SSE Implementation) — CWE-400
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Patched: 1.4.0 — 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-400) exists in Abacus SSE Implementation.
Check the vendor advisory for the affected versions of Abacus SSE Implementation.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 1.4.0.
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. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Abacus SSE Implementation を使っているサービスとバージョンを洗い出す。
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2Apply patch patch
Upgrade Abacus SSE Implementation to 1.4.0ステージング環境で 1.4.0 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。
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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。
References
- advisory github.com
- advisory github.com
- advisory nvd.nist.gov
- patch github.com