Pages belonging to largepage shared memory objects were not explicitly wired. When sendfile(2) transmitted such an object with the SF_NOCACHE flag, it freed the underlying pages after transmission even though existing mappings still referred to them.
An unprivileged local user can abuse the bug to access freed kernel memory. This can be exploited to escalate privileges.
Metrics
Affected Vendors & Products
References
History
Tue, 01 Sep 2026 22:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| CPEs | cpe:2.3:o:freebsd:freebsd:14.3:-:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.3:p10:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.3:p11:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.3:p12:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.3:p13:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.3:p14:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.3:p15:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.3:p1:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.3:p2:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.3:p3:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.3:p4:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.3:p5:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.3:p6:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.3:p7:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.3:p8:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.3:p9:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.4:-:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.4:p1:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.4:p2:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.4:p3:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.4:p4:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.4:p5:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.4:p6:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:14.4:rc1:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:15.0:-:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:15.0:p10:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:15.0:p1:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:15.0:p2:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:15.0:p3:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:15.0:p4:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:15.0:p5:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:15.0:p6:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:15.0:p7:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:15.0:p8:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:15.0:p9:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:15.1:-:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:15.1:rc2:*:*:*:*:*:* cpe:2.3:o:freebsd:freebsd:15.1:rc3-p1:*:*:*:*:*:* |
Fri, 21 Aug 2026 16:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
ssvc
|
Thu, 20 Aug 2026 19:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
cvssV3_1
|
Wed, 19 Aug 2026 13:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Freebsd
Freebsd freebsd |
|
| Vendors & Products |
Freebsd
Freebsd freebsd |
Wed, 19 Aug 2026 06:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Pages belonging to largepage shared memory objects were not explicitly wired. When sendfile(2) transmitted such an object with the SF_NOCACHE flag, it freed the underlying pages after transmission even though existing mappings still referred to them. An unprivileged local user can abuse the bug to access freed kernel memory. This can be exploited to escalate privileges. | |
| Title | posixshm: largepage shared memory objects not explicitly wired | |
| Weaknesses | CWE-826 | |
| References |
|
Status: PUBLISHED
Assigner: freebsd
Published: 2026-08-19T05:56:53.494Z
Updated: 2026-08-20T18:35:54.694Z
Reserved: 2026-05-29T20:24:28.616Z
Link: CVE-2026-49427
Updated: 2026-08-20T18:35:51.151Z
Status : Analyzed
Published: 2026-08-19T06:17:41.977
Modified: 2026-09-01T20:06:01.460
Link: CVE-2026-49427
No data.