Vulnerability in Snappier (CVE-2026-44302)
Summary
Vulnerability in Snappier (CVE-2026-44302). Risk of unauthorized operations or information disclosure. Exploitable via Snappier.SnappyStream. Mitigation: upgrade to 1.3.1 or later.
Original description
The description as published by the source.
Summary
Snappier.SnappyStream enters an uncatchable infinite loop when decompressing a malformed framed-format Snappy stream as small as 15 bytes.
Details
The hang manifests as a userspace busy loop with SnappyStreamDecompressor.Decompress repeatedly calling Crc32CAlgorithm.Append. The exact non-terminating loop in or above Decompress has not been traced further.
PoC
using System.IO.Compression;
using Snappier;
byte[] data = { 0x00, 0x04, 0x00, 0x00, 0x64, 0x4e, 0x6c, 0x71, 0x79, 0x20, 0x77, 0x6f, 0x72, 0x6c, 0x64 };
using var src = new MemoryStream(data);
using var snap = new SnappyStream(src, CompressionMode.Decompress);
using var dst = new MemoryStream();
snap.CopyTo(dst); // never returns
Impact
A caller using SnappyStream on attacker-controlled bytes can be made to spin forever and burn a thread until the process is killed. try/catch around the stream operation can't recover (no exception is thrown).
Source: NIST National Vulnerability Database NVD GitHub Advisory
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-2026-44302 has been found in Snappier.
Attackers can target a specific entry point like Snappier.SnappyStream over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 7.5/10.
What to do: upgrade Snappier to 1.3.1 or later.
If unsure, ask your IT team or search "Snappier CVE-2026-44302" on the vendor's site.
CVE-2026-44302 (Snappier) — CWE-835 / CVSS v3 7.5
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: Snappier.SnappyStream / SnappyStream
Patched: 1.3.1 — 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-835) exists in Snappier. Attackers reach the vulnerable code path via Snappier.SnappyStream without authentication.
Check the vendor advisory for the affected versions of Snappier. Attack surface: Snappier.SnappyStream / SnappyStream.
Severity: High (CVSS 7.5/10). Risk of unauthorized operations or information disclosure.
Update to 1.3.1.
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 'Snappier' . 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 'Snappier' . | 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
Snappier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 Snappier to 1.3.1ステージング環境で 1.3.1 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