Coverage › CVE-2026-46300
CVE-2026-46300 Unmapped
Linux Kernel Missing Initialization of a Variable Vulnerability
- Vendor / product
- Linux — Kernel
- Description (CISA)
- Linux Kernel contains a missing initialization of a variable vulnerability that could allow for unintended modification of page-cache-backed data via failure to preserve the shared-fragment marker during socket buffer coalescing, causing ESP input processing to decrypt shared fragments in place. This vulnerability can be chained with CVE-2026-109618 and CVE-2026-109619 to implant PHP webshells and run commands as root.
- Added to KEV
- 2026-10-28 — after the latest CTID mapping snapshot (2025-07-28)
- Due date
- 2026-10-31
- Required action
- Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
- Known ransomware use
- Unknown
- Forensic triage (CISA)
- Yes
- CWE
- CWE-456
- CISA notes
- This vulnerability affects an open-source component, third-party library, protocol, or proprietary implementation that could be used by different products. For more information, please see:
https://git.kernel.org/stable/c/3599e6b3cc1ada96883d496a50a210d3afbb6987
https://git.kernel.org/stable/c/2f2b16022a2e10ca7bccfb98db5ed2ec0f72641c
https://git.kernel.org/stable/c/9d3e5fd19fe1063bf607219e8562fbd567b8e8d5
https://git.kernel.org/stable/c/78bf6b6bb19541d19fbda6242e7cfe2c682763c0
https://git.kernel.org/stable/c/760e1addc27ba1a7beb4a0a7e8b3e9ec49e7a34e
https://git.kernel.org/stable/c/3bd9e113d50034db99d7ef69fd8e5242d15e414a
https://git.kernel.org/stable/c/3884358a9286b17f389a72b1426fc4547c23c111
https://git.kernel.org/stable/c/f84eca5817390257cef78013d0112481c503b4a3
BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk
Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk
https://nvd.nist.gov/vuln/detail/CVE-2026-46300 - Elsewhere
- cve.org · NVD · CISA KEV · JSON
ATT&CK techniques
No public source states how this vulnerability is exploited in ATT&CK terms.
The only authoritative CVE → ATT&CK mapping in the open — CTID's Mappings Explorer, pinned to a KEV snapshot of 2025-07-28 and ATT&CK 16.1 — does not include CVE-2026-46300. This entry was added to KEV on 2026-10-28, after that snapshot; of the 371 entries added since, 0 have a mapping. CISA's catalogue carries no technique field. kevmap does not infer techniques from the CWE (CWE-456) — here is why — and does not guess.
This page will change state automatically if a mapping is published. What is shown above is everything CISA publishes about the entry.