Security readout for executives and security teams
Plain-English summary
A remote, unauthenticated client can repeatedly connect to a Linux ksmbd file server until its connection capacity is exhausted. Legitimate users may then be unable to access SMB shares. The issue affects availability, not confidentiality or data integrity, according to the supplied CVSS assessment.
Executive priority
Prioritize internet-facing or broadly reachable ksmbd servers for rapid remediation. Internal-only systems still warrant scheduled patching because any reachable unauthenticated client could disrupt file-sharing availability. Business urgency depends on SMB service criticality and network exposure.
Technical view
CVE-2025-38501 is a CWE-400 resource-exhaustion flaw in Linux kernel ksmbd. Repeated connections from one source IP can consume the maximum connection allowance and block other clients. It is network-accessible, low-complexity, requires no privileges or user interaction, and has a CVSS 3.1 score of 7.5.
Likely exposure
Exposure is limited to systems running ksmbd, particularly where SMB is reachable from untrusted networks. The bundle lists Linux versions 5.15, 6.1.148, 6.6.102, 6.12.42, 6.15.10, 6.16.1, and 6.17 as affected. Distribution package status must be confirmed separately.
Exploitation context
A public repository named KSMBDrain is referenced, indicating public exploit-related research or tooling. However, the supplied record does not establish real-world attacks, and the CVE is not listed in KEV. Treat practical abuse as plausible without claiming active exploitation.
Researcher notes
The fix limits repeated connections from the same IP. Six Linux stable commits are supplied, suggesting backports across kernel branches, but the bundle does not map each commit to a specific release. The affected-version data also contains ambiguous commit-hash entries, so use distribution advisories and commit inclusion checks for authoritative host-level decisions.
Mitigation direction
- Update to a vendor-supported kernel containing the applicable upstream ksmbd fix.
- Check Linux distribution advisories for the corrected package version for each deployed release.
- Restrict SMB access to trusted networks and clients until affected systems are updated.
- Disable ksmbd where SMB file-serving functionality is unnecessary.
Validation and detection
- Inventory hosts running or configured to load ksmbd.
- Identify each host's exact kernel and distribution package version.
- Verify SMB network reachability from untrusted or unnecessary network segments.
- Confirm the installed kernel includes the applicable referenced stable fix.
- Monitor for connection saturation or abnormal repeated connections from individual addresses.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-400: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2025-38501 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
2 official scoresWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H3.93.6LinuxCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H3.93.6CISA-ADPVulnerability scoring details
Base CVSS 3.1 score
7.5HighVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Base CVSS 3.1 score
7.5HighVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://git.kernel.org/stable/c/cb092fc3a62972a4aa47c9fe356c2c6a01cd840bCVE reference, Linux
- https://git.kernel.org/stable/c/fa1c47af4ff641cf9197ecdb1f8240cbb30389c1CVE reference, Linux
- https://git.kernel.org/stable/c/7e5d91d3e6c62a9755b36f29c35288f06c3cd86bCVE reference, Linux
- https://git.kernel.org/stable/c/f1ce9258bcbce2491f9f71f7882b6eed0b33ec65CVE reference, Linux
- https://git.kernel.org/stable/c/6073afe64510c302b7a0683a01e32c012eff715dCVE reference, Linux
- https://git.kernel.org/stable/c/e6bb9193974059ddbb0ce7763fa3882bd60d4dc3CVE reference, Linux
- https://github.com/keymaker-arch/KSMBDrainCVE reference, CVE
- https://lists.debian.org/debian-lts-announce/2025/10/msg00008.htmlCVE reference, CVE
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.