CVE-2026-15449
TOCTOU double copyin in illumos dld ioctl handling causes kernel heap corruption
Description
A time-of-check to time-of-use (TOCTOU) flaw in the illumos data-link pseudo-driver (dld) affects handling of the DLDIOC_GETMACPROP and DLDIOC_SETMACPROP ioctls on /dev/dld. drv_ioc_prop_common() in usr/src/uts/common/io/dld/dld_drv.c copies the dld_ioc_macprop_t ioctl header in once to read its pr_valsize field, sizes and allocates a kernel heap buffer from that value, and then copies the full request in a second time from the same unprivileged user address. A concurrent thread can enlarge pr_valsize between the two copyins, so the second copyin and the subsequent property handling write beyond the end of the undersized allocation and corrupt the kernel heap. An unprivileged local user, including one confined to a non-global zone that owns a datalink, can trigger this to panic the system. The resulting kernel heap corruption may be usable for further compromise.
INFO
Published Date :
July 16, 2026, 8:16 p.m.
Last Modified :
July 16, 2026, 8:16 p.m.
Remotely Exploit :
No
Source :
0ca53633-f0b5-4853-ba72-e0a2e62000d0
Affected Products
The following products are affected by CVE-2026-15449
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | MEDIUM | 0ca53633-f0b5-4853-ba72-e0a2e62000d0 | ||||
| CVSS 4.0 | MEDIUM | 0ca53633-f0b5-4853-ba72-e0a2e62000d0 |
Solution
- Update illumos to patch the dld driver.
- Validate ioctl header size before allocation.
- Ensure atomic handling of ioctl data.
- Limit local user access to /dev/dld.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-15449.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-15449 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-2026-15449
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-15449 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-15449 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by 0ca53633-f0b5-4853-ba72-e0a2e62000d0
Jul. 16, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://github.com/illumos/illumos-gate', 'vendor': 'illumos', 'modules': ['kernel', 'dld'], 'product': 'illumos-gate', 'versions': [{'status': 'affected', 'changes': [{'at': '6959feb5b430411a4809b06c53dcdb42fb525eac', 'status': 'unaffected'}], 'version': 'eae72b5b807baa9116e64502cbb278edf15f3146', 'lessThan': '6959feb5b430411a4809b06c53dcdb42fb525eac', 'versionType': 'git'}], 'programFiles': ['usr/src/uts/common/io/dld/dld_drv.c', 'usr/src/uts/common/sys/dld.h'], 'defaultStatus': 'affected'}, {'vendor': 'OmniOS', 'product': 'OmniOS', 'versions': [{'status': 'affected', 'version': 'any', 'lessThan': 'r151054', 'versionType': 'custom'}, {'status': 'affected', 'changes': [{'at': 'r151058j', 'status': 'unaffected'}], 'version': 'r151058', 'lessThan': 'r151058j', 'versionType': 'custom'}, {'status': 'affected', 'changes': [{'at': 'r151056aj', 'status': 'unaffected'}], 'version': 'r151056', 'lessThan': 'r151056aj', 'versionType': 'custom'}, {'status': 'affected', 'changes': [{'at': 'r151054bj', 'status': 'unaffected'}], 'version': 'r151054', 'lessThan': 'r151054bj', 'versionType': 'custom'}], 'defaultStatus': 'affected'}, {'vendor': 'Triton Data Center', 'product': 'SmartOS', 'versions': [{'status': 'affected', 'changes': [{'at': '20260709', 'status': 'unaffected'}], 'version': 'any', 'lessThan': '202060709', 'versionType': 'custom'}], 'defaultStatus': 'affected'}] Added Description A time-of-check to time-of-use (TOCTOU) flaw in the illumos data-link pseudo-driver (dld) affects handling of the DLDIOC_GETMACPROP and DLDIOC_SETMACPROP ioctls on /dev/dld. drv_ioc_prop_common() in usr/src/uts/common/io/dld/dld_drv.c copies the dld_ioc_macprop_t ioctl header in once to read its pr_valsize field, sizes and allocates a kernel heap buffer from that value, and then copies the full request in a second time from the same unprivileged user address. A concurrent thread can enlarge pr_valsize between the two copyins, so the second copyin and the subsequent property handling write beyond the end of the undersized allocation and corrupt the kernel heap. An unprivileged local user, including one confined to a non-global zone that owns a datalink, can trigger this to panic the system. The resulting kernel heap corruption may be usable for further compromise. Added CVSS V4.0 AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-122 Added CWE CWE-367 Added Reference https://github.com/illumos/illumos-gate/commit/6959feb5b430411a4809b06c53dcdb42fb525eac Added Reference https://illumos.org/issues/18020 Added Reference https://illumos.topicbox.com/groups/developer/T923147fae854a738-M03c29e1be33dac2a5e3d9535/18020-double-copyin-of-dldioc-consumers