CVE-2026-90048

CRITICAL CVSS 9.8
Published: 2026-09-16
Modified: 2026-09-16
Enriched via mock
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AI Threat Summary

CVE-2026-90048 is a moderate vulnerability affecting the target software. Threat hunters should monitor for exploit attempts and apply vendor patches immediately.

Description

In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: fix slab-out-of-bounds write in ni_create_attr_list() ni_create_attr_list() allocates a fixed buffer of al_aligned(record_size) (== record_size) bytes and then walks every attribute of the primary MFT record, writing one ATTR_LIST_ENTRY per attribute and advancing the cursor by le_size(name_len), with no check against the end of the buffer; the total size is only computed after the loop. A minimum-size resident attribute occupies SIZEOF_RESIDENT (0x18 = 24) bytes on disk, but an unnamed attribute expands to le_size(0) (0x20 = 32) bytes in the list. Because the number of attributes in a record is not bounded (mi_enum_attr() accepts arbitrarily many equal-type, nameless minimum-size attributes), a crafted record packed with such attributes produces a list larger than record_size and overflows the heap buffer. This is reachable from a crafted, loop-mounted NTFS image: opening the file and adding an attribute (e.g. via setxattr) drives ntfs_set_ea() -> ni_insert_resident() -> ni_insert_attr() -> ni_ins_attr_ext() -> ni_create_attr_list(). BUG: KASAN: slab-out-of-bounds in ni_create_attr_list+0xc48/0x1058 Write of size 4 at addr ffff000008984c00 by task setfattr/345 ni_create_attr_list+0xc48/0x1058 ni_ins_attr_ext+0x510/0x7c0 ni_insert_attr+0x3f8/0x70c ni_insert_resident+0xc8/0x3b0 ntfs_set_ea+0x66c/0xd28 ntfs_setxattr+0x4d8/0x5b0 __arm64_sys_setxattr+0xa4/0x124 Allocated by task 345: ni_create_attr_list+0x188/0x1058 The buggy address belongs to the cache kmalloc-1k of size 1024 (the write lands at object+1024). Size the buffer from the actual attributes instead of assuming a single record_size is always enough.

Attack Chain
1
Reconnaissance

Attacker scans for vulnerable versions using version banners or PoC scanners

2
Initial Access

Attacker triggers CVE-2026-90048 vulnerability with a crafted request or payload

3
Execution

Vulnerability exploited to perform unauthorized actions on the target system

4
Impact

Depending on vulnerability type, attacker achieves data access, service disruption, or code execution

MITRE ATT&CK Techniques
T1190 Exploit Public-Facing Application
Initial Access

Public-facing application vulnerability exploited for initial access

T1203 Exploitation for Client Execution
Execution

Vulnerability exploited to execute attacker-controlled code

Indicators of Compromise
Type Value Description
user_agent Mozilla/5.0 (compatible; exploit/1.0) Generic exploit scanner user agent pattern
url /api/vuln-endpoint?payload=<malicious> Exploit attempt against application endpoint — monitor access logs for anomalous params
Remediation
1. Apply vendor-supplied security patches immediately. 2. If patches are unavailable, apply recommended mitigations from the vendor advisory. 3. Enable WAF rules or IDS signatures to detect exploitation attempts. 4. Monitor logs for indicators of compromise listed above. 5. Implement network segmentation to limit blast radius if exploitation occurs. 6. Subscribe to vendor security advisories for this product.
Quick Facts
CVE ID CVE-2026-90048
CVSS Score 9.8
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Published 2026-09-16
Exploited No
CISA KEV No
PoC Not public
References
External Resources
NVD Entry BleepingComputer The Hacker News