Mongoose: ppp_handle_ipv6cp() uses attacker-controlled length without bounds check — OOB read and heap overflow (PPP/PPPoE, MG_ENABLE_IPV6)
CVSS score
8.8
EPSS probability
—
Risk score
0.9
Published
9 h ago
Etkilenen ürün ve sürüm için yayımlanan güvenlik güncellemesini uygulayın.
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Vulnerability description
CVE AI research
DayBreach AI Explanation
Verified against sourcesSources read
1
Source agreement
Tam uyum
Evidence confidence
%55
Short explanation
Prior to version 7.23 of Mongoose, ppp_handle_ipv6cp() trusts the IPv6CP length field without bounds checking. This flaw allows an adjacent peer to trigger out-of-bounds reads, heap overflows, or event loop hangs.
An unauthenticated adjacent attacker can exploit this high-severity vulnerability to expose sensitive memory, crash the target, or compromise memory integrity.
What should be done?
- Update Mongoose to version 7.23 or later
- Follow the vendor advisory guidelines
- Review PPP/PPPoE configurations and feature flags
Chain of evidence and sources
Mongoose sürüm 7.23 öncesinde ppp_handle_ipv6cp() fonksiyonu IPv6CP uzunluk alanını gelen yük boyutuyla karşılaştırmadan güvenir.
Yetkilendirilmemiş bitişik bir eş, kısa bir Yapılandırma İsteği göndererek sınır dışı okuma ve yığın taşması tetikleyebilir.
İlgili güvenlik açığı 7.23 sürümünde giderilmiştir.
Show the technical text from the sources
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.
CVSS vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE: CWE-122, CWE-125
Explanation produced with the local gemini-flash-lite-latest model. Numerical metrics and the KEV, patch and exploit statuses are not determined by AI.
IMPACT: Affected Products and Software
Affected Products
The following products are affected by CVE-2026-63626 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.
RED HAT CSAF/VEX: Product Impact Check
SCORING: CVSS from Multiple Sources
CVSS Scores
The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.
| SCORE | VERSION | SEVERITY | VECTOR | SOURCE |
|---|---|---|---|---|
| 8.8 | CVSS V31 | HIGH | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H | NVD |
| 8.8 | CVSS V3_1 | HIGH | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H | CVE CNA |
Patch and Remediation Guide
Solution & Remediation Advisory
1 doğrulanmış yama veya düzeltilmiş sürüm kanıtı bulundu.
7.23+ds-1Ubuntu upstream: 7.23+ds-1
Public exploit and active exploitation status
Verified exploit intelligence
No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.
Weakness Classification and Attack Patterns (CWE & CAPEC)
CWE - Common Weakness Enumeration
While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-63626 is associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-63626 weaknesses.
Attack Vector and Accessibility
Official Sources and Advisories
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