Vulnerability in Mongoose (CVE-2026-63626)
Summary
Vulnerability in Mongoose (CVE-2026-63626). Successful exploitation can lead to full system takeover. Exploitable via len. Mitigation: upgrade to 7.22 or later.
Original description
The description as published by the source.
Mongoose is an embedded web server and network library. Prior to 7.23, ppp_handle_ipv6cp() in src/l2_ppp.c trusts the 16-bit IPv6CP len field without checking it against the received payload size. On a PPP or PPPoE link using MG_ENABLE_TCPIP and MG_ENABLE_IPV6, an unauthenticated adjacent peer can complete the required LCP exchange and send a short Configure-Request with an oversized length, causing ppp_tx_frame() to read beyond recv_queue.buf and write beyond tx.buf. The same length misuse can also expose adjacent heap bytes in a reply or hang the event loop through find_opt(). This issue is fixed in version 7.23.
Source: NIST National Vulnerability Database NVD
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-2026-63626 has been found in Mongoose.
Attackers can target a specific entry point like len over the network to misuse the product.
Successful exploitation can lead to full system takeover. CVSS score: 8.8/10.
What to do: upgrade Mongoose to 7.22 or later.
If unsure, ask your IT team or search "Mongoose CVE-2026-63626" on the vendor's site.
CVE-2026-63626 (Mongoose) — CWE-122 / CVSS v3 8.8
Attack vector: adjacent-network / unauthenticated / no user interaction
Attack surface: len / recv_queue.buf / tx.buf / mongoose.c
Affected: <= 7.22
Patched: 7.22 — 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-122) exists in Mongoose. Attackers reach the vulnerable code path via len without authentication.
Affected versions of Mongoose: <= 7.22. Attack surface: len / recv_queue.buf / tx.buf / mongoose.c.
Severity: High (CVSS 8.8/10). Successful exploitation can lead to full system takeover.
Update to 7.22. (If a vulnerable version <= 7.22 is in production, plan an immediate maintenance window.)
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 'Mongoose' . 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 'Mongoose' . | 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
Mongooseを grep し、稼働しているサービス・バージョンを把握する。 -
2Match against affected range verify
Confirm if version satisfies `<= 7.22`Step 1 で見つかったバージョンが影響範囲
<= 7.22に該当するか照合。本番で稼働中ならインシデント扱い。 -
3Apply patch patch
Upgrade Mongoose to 7.22ステージング環境で 7.22 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。
-
4Post-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。