CVE-2026-63923
octeontx2-af: validate body pcifunc in rvu_mbox_handler_rep_event_notify
Description
In the Linux kernel, the following vulnerability has been resolved: octeontx2-af: validate body pcifunc in rvu_mbox_handler_rep_event_notify rvu_mbox_handler_rep_event_notify() in drivers/net/ethernet/marvell/ octeontx2/af/rvu_rep.c queues a sender-controlled REP_EVENT_NOTIFY request body verbatim, and rvu_rep_up_notify() then forwards event->pcifunc (the nested body field, distinct from the AF-normalised header pcifunc) into rvu_get_pfvf(), rvu_get_pf() and the AF->PF mailbox device index without any bounds check. A VF attached to a PF that has been put into switchdev representor mode reaches this path: the VF mailbox handler otx2_pfvf_mbox_handler() forwards every message id including MBOX_MSG_REP_EVENT_NOTIFY to AF without an allowlist, and the AF dispatcher rewrites only msg->pcifunc, leaving struct rep_event::pcifunc attacker-controlled. The sibling rvu_mbox_handler_esw_cfg() refuses requests whose header pcifunc is not rvu->rep_pcifunc; this handler has no equivalent gate. An out-of-range body pcifunc selects an &rvu->pf[]/&rvu->hwvf[] element past the allocated array and, for RVU_EVENT_MAC_ADDR_CHANGE, turns into a six-byte attacker-chosen OOB ether_addr_copy() target inside the queued worker; KASAN reports a slab-out-of-bounds write in rvu_rep_wq_handler. Reject malformed requests at the handler entry by gating on is_pf_func_valid(), which is already the canonical PF/VF range check in this driver; expose it via rvu.h so callers in rvu_rep.c can use it instead of open-coding the same range arithmetic.
INFO
Published Date :
July 19, 2026, 4:17 p.m.
Last Modified :
Aug. 3, 2026, 10:16 a.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
Solution
- Reject malformed requests at handler entry.
- Gate requests using is_pf_func_valid().
- Expose is_pf_func_valid() via rvu.h.
- Use range check instead of open-coded arithmetic.
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-2026-63923.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-63923 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-2026-63923
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-2026-63923 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-63923 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.
-
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 03, 2026
Action Type Old Value New Value Added Reference https://git.kernel.org/stable/c/4467fa514482bbce82f73788943c815f3d126ab3 Changed Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'b8fea84a0468404fe3b3327ad54d583950be9dec', 'lessThan': '68be0260e2a02ff9b18a8678d5f8d1715fa20138', 'versionType': 'git'}, {'status': 'affected', 'version': 'b8fea84a0468404fe3b3327ad54d583950be9dec', 'lessThan': '2156a29aecfffa2eb7c558255690084efbe9f3b0', 'versionType': 'git'}], 'programFiles': ['drivers/net/ethernet/marvell/octeontx2/af/rvu.c', 'drivers/net/ethernet/marvell/octeontx2/af/rvu.h', 'drivers/net/ethernet/marvell/octeontx2/af/rvu_rep.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.13'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.13', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '7.0.12', 'versionType': 'semver', 'lessThanOrEqual': '7.0.*'}, {'status': 'unaffected', 'version': '7.1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['drivers/net/ethernet/marvell/octeontx2/af/rvu.c', 'drivers/net/ethernet/marvell/octeontx2/af/rvu.h', 'drivers/net/ethernet/marvell/octeontx2/af/rvu_rep.c'], 'defaultStatus': 'affected'}] [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'b8fea84a0468404fe3b3327ad54d583950be9dec', 'lessThan': '4467fa514482bbce82f73788943c815f3d126ab3', 'versionType': 'git'}, {'status': 'affected', 'version': 'b8fea84a0468404fe3b3327ad54d583950be9dec', 'lessThan': '68be0260e2a02ff9b18a8678d5f8d1715fa20138', 'versionType': 'git'}, {'status': 'affected', 'version': 'b8fea84a0468404fe3b3327ad54d583950be9dec', 'lessThan': '2156a29aecfffa2eb7c558255690084efbe9f3b0', 'versionType': 'git'}], 'programFiles': ['drivers/net/ethernet/marvell/octeontx2/af/rvu.c', 'drivers/net/ethernet/marvell/octeontx2/af/rvu.h', 'drivers/net/ethernet/marvell/octeontx2/af/rvu_rep.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.13'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.13', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.18.42', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.0.12', 'versionType': 'semver', 'lessThanOrEqual': '7.0.*'}, {'status': 'unaffected', 'version': '7.1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['drivers/net/ethernet/marvell/octeontx2/af/rvu.c', 'drivers/net/ethernet/marvell/octeontx2/af/rvu.h', 'drivers/net/ethernet/marvell/octeontx2/af/rvu_rep.c'], 'defaultStatus': 'affected'}] -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jul. 20, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jul. 19, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'b8fea84a0468404fe3b3327ad54d583950be9dec', 'lessThan': '68be0260e2a02ff9b18a8678d5f8d1715fa20138', 'versionType': 'git'}, {'status': 'affected', 'version': 'b8fea84a0468404fe3b3327ad54d583950be9dec', 'lessThan': '2156a29aecfffa2eb7c558255690084efbe9f3b0', 'versionType': 'git'}], 'programFiles': ['drivers/net/ethernet/marvell/octeontx2/af/rvu.c', 'drivers/net/ethernet/marvell/octeontx2/af/rvu.h', 'drivers/net/ethernet/marvell/octeontx2/af/rvu_rep.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.13'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.13', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '7.0.12', 'versionType': 'semver', 'lessThanOrEqual': '7.0.*'}, {'status': 'unaffected', 'version': '7.1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['drivers/net/ethernet/marvell/octeontx2/af/rvu.c', 'drivers/net/ethernet/marvell/octeontx2/af/rvu.h', 'drivers/net/ethernet/marvell/octeontx2/af/rvu_rep.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: octeontx2-af: validate body pcifunc in rvu_mbox_handler_rep_event_notify rvu_mbox_handler_rep_event_notify() in drivers/net/ethernet/marvell/ octeontx2/af/rvu_rep.c queues a sender-controlled REP_EVENT_NOTIFY request body verbatim, and rvu_rep_up_notify() then forwards event->pcifunc (the nested body field, distinct from the AF-normalised header pcifunc) into rvu_get_pfvf(), rvu_get_pf() and the AF->PF mailbox device index without any bounds check. A VF attached to a PF that has been put into switchdev representor mode reaches this path: the VF mailbox handler otx2_pfvf_mbox_handler() forwards every message id including MBOX_MSG_REP_EVENT_NOTIFY to AF without an allowlist, and the AF dispatcher rewrites only msg->pcifunc, leaving struct rep_event::pcifunc attacker-controlled. The sibling rvu_mbox_handler_esw_cfg() refuses requests whose header pcifunc is not rvu->rep_pcifunc; this handler has no equivalent gate. An out-of-range body pcifunc selects an &rvu->pf[]/&rvu->hwvf[] element past the allocated array and, for RVU_EVENT_MAC_ADDR_CHANGE, turns into a six-byte attacker-chosen OOB ether_addr_copy() target inside the queued worker; KASAN reports a slab-out-of-bounds write in rvu_rep_wq_handler. Reject malformed requests at the handler entry by gating on is_pf_func_valid(), which is already the canonical PF/VF range check in this driver; expose it via rvu.h so callers in rvu_rep.c can use it instead of open-coding the same range arithmetic. Added Reference https://git.kernel.org/stable/c/2156a29aecfffa2eb7c558255690084efbe9f3b0 Added Reference https://git.kernel.org/stable/c/68be0260e2a02ff9b18a8678d5f8d1715fa20138