Kernel warning via duplicate SMB credit returns
Published Oct 18, 2026 · Updated Oct 18, 2026
Credit accounting errors in the Linux SMB client allow attackers to trigger a kernel warning via failed compound-request sends. compound_send_recv() leaves request entries on pending_mid_q when unlocking after a send failure, allowing reconnect callbacks and the send-error path to return the same credits and decrement in_flight twice. Reachability requires SMB client activity and a socket send failure; the documented consequence is a warning in smb2_add_credits(), with attacker control and further impact unspecified.
Summary
What happened
Credit accounting errors in the Linux SMB client allow attackers to trigger a kernel warning via failed compound-request sends. compound_send_recv() leaves request entries on pending_mid_q when unlocking after a send failure, allowing reconnect callbacks and the send-error path to return the same credits and decrement in_flight twice. Reachability requires SMB client activity and a socket send failure; the documented consequence is a warning in smb2_add_credits(), with attacker control and further impact unspecified.
The record
- CVE
- CVE-2026-98449
- Published
- Oct 18, 2026
- Updated
- Oct 18, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- Unavailable
- Attack vector
- Unavailable
- Privileges
- Unavailable
Timeline
How it unfolded
- Oct 18, 2026CVE publishedPublication date reported by the CVE source.
- Oct 18, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=3c57a0be487088b08d9c88998f911eb4a7ba36e4
- Affected versionversion=4.20.11 <4.21
- Affected versionversion=5.0
- Affected versionversion=ee258d79159afed52ca9372aeb9c1a51e89b32ee <70783946f3b5d0c06ec7df0f5e7bec2bfad24efb
- Affected versionversion=ee258d79159afed52ca9372aeb9c1a51e89b32ee <8f6f8a48399f82f4a83f7b9f25b9707e0062a4f9
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Activity data is delayed. The latest report is Sep 28, 2026.
Weakness, pattern, technique
No sourced classifications are available.
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Get started to see how Hinoki identifies affected software and validates exploitability in your environment.
Get started