ksmbd: follow SMB2 session expiration semantics
CVSS score
—
EPSS probability
%0.2
Risk score
—
Published
4 d ago
Resmî kaynaklarda yeterli kanıt bulunamadı. Bu sonuç “yama yok” anlamına gelmez.
Impact on My Inventory
Only the personal products you have added to your account are assessed; an organisation's inventory does not appear here.
Checking session…
Vulnerability description
CVE AI research
DayBreach AI Explanation
Verified against sourcesSources read
2
Source agreement
Tam uyum
Evidence confidence
%63
Short explanation
The ksmbd component in the Linux kernel contains a vulnerability involving the misinterpretation of SMB2 session expiration semantics, leading to the premature destruction of valid sessions.
This flaw can cause unexpected session deletions and mapped drive failures, resulting in service disruptions.
What should be done?
- Follow vendor advisories for patch status
- Apply the relevant Linux kernel updates
Chain of evidence and sources
ksmbd_session_register() fonksiyonu, istemci yeni bir SessionSetup değişimi başlattığında on saniye sonra geçerli oturumları yok etmektedir.
Bu durum tree connects bağlantılarını geçersiz kılmakta ve eşlenmiş sürücülerin STATUS_NETWORK_NAME_DELETED hatası vermesine sebep olmaktadır.
Show the technical text from the sources
In the Linux kernel, the following vulnerability has been resolved: ksmbd: follow SMB2 session expiration semantics ksmbd_session_register() destroys valid sessions after ten seconds of inactivity whenever a client starts another SessionSetup exchange. This confuses Session.IdleTime with Session.ExpirationTime. Windows can create additional authenticated sessions on an existing connection, so deleting the older session invalidates its tree connects and makes mapped drives fail with STATUS_NETWORK_NAME_DELETED. The session expiration rules require the server to change a valid session to expired only after its credential expiration time passes. A valid or expired session otherwise keeps its connection from being scavenged. Connections that have not negotiated a dialect, have no sessions, or have only InProgress sessions are disconnected after an implementation-specific timeout. Use the Windows-compatible 45 second value and run the expiration check periodically for both TCP and SMB Direct. Keep zero as an infinite credential expiration time, and count each Valid-to-Expired transition. Set expired sessions to InProgress when they reauthenticate. If authentication fails, remove the session from the global and per-connection tables immediately, including SMB3 multichannel connections. Retain protection against abandoned SessionId-zero exchanges by allowing only one InProgress authentication per connection. Additional exchanges fail with STATUS_INSUFFICIENT_RESOURCES, and stale InProgress sessions are reaped after the same 45 second setup timeout. This bounds the original unauthenticated memory-exhaustion path without evicting established sessions.
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
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 |
|---|---|---|---|---|
| The sources have not yet published a verified CVSS metric. | ||||
Patch and Remediation Guide
Solution & Remediation Advisory
İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.
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-2026-98420 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-2026-98420 weaknesses.
Official Sources and Advisories
Yama durumu bilinmiyor
Similar Vulnerabilities
Get this vulnerability through the API
Affected products, version ranges, exploitation status and patch information in a single request, with a free key.
curl -H "x-api-key: $DAYBREACH_API_KEY" \ "https://api.daybreach.dev/api/v1/intel/cves/CVE-2026-98420"