VulnerabilityPublished 25 Jun 2026Updated 2 Jul 2026

CVE-2026-53204: Linux kernel · NULL Pointer Dereference

Source GCVE Database

Not known to be exploited · CVSS 5.5 Medium.

Data as of 26 Oct 2026, 14:05 UTC

CVSS 3.1 base score

5.5Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.1% chance of exploitation in 30 days – higher than 3% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Attack Vector: Local
Attack Complexity: Low
Privileges Required: Low
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: High

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Local: The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Either: the attacker exploits the vulnerability by accessing the target system locally (e.g., keyboard, console), or remotely (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., tricking a legitimate user into opening a malicious document).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 25 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

ghsa-7vgh-484p-pv5r

What to do

AI-suggested

Until a patch is available, avoid using the affected functionality if possible or apply any vendor-recommended workarounds once published.

Description

In the Linux kernel, the following vulnerability has been resolved: firmware: stratix10-rsu: Fix NULL deref on rsu_send_msg() timeout in probe rsu_send_msg() can return -ETIMEDOUT when wait_for_completion_interruptible_timeout() fires while the SMC call is still pending. In stratix10_rsu_probe(), the error paths for COMMAND_RSU_DCMF_VERSION, COMMAND_RSU_DCMF_STATUS, COMMAND_RSU_MAX_RETRY and COMMAND_RSU_GET_SPT_TABLE call stratix10_svc_free_channel() - which sets chan->scl to NULL - but then fall through and queue the next request on the same channel. The next svc kthread that runs will dereference pdata->chan->scl in its receive callback path, triggering a NULL pointer dereference identical to the one fixed by commit c45f7263100c ("firmware: stratix10-rsu: Fix NULL pointer dereference when RSU is disabled") for the COMMAND_RSU_STATUS path. Apply the same cleanup pattern to the remaining failure paths: remove the async client, free the channel, and return early so no further messages are queued on a channel whose scl has been cleared. While at it, clean up stratix10_rsu_probe() in two ways without changing behavior: - Drop redundant zero-initialization of fields already cleared by devm_kzalloc(): client.receive_cb, status.* and spt0/1_address (INVALID_SPT_ADDRESS is 0x0). - Replace five identical 3-line error-cleanup blocks (stratix10_svc_remove_async_client() + stratix10_svc_free_channel() + return ret) with goto labels (remove_async_client, free_channel), matching the standard kernel resource-unwinding pattern and making it easier to extend the probe sequence without forgetting matching cleanup. Also move init_completion() next to mutex_init() so sync-primitive initialization is grouped before anything that could trigger a callback. --- v2: Add a minor clean-up of the function stratix10_rsu_probe() to have a centralize exit for all the rsu_send_async_msg() and rsu_send_msg().

Impact

The vulnerability results in a NULL pointer dereference causing a denial of service (kernel crash or instability) in the Linux kernel when the stratix10-rsu driver is used. There is no impact on confidentiality or integrity reported.

Summary

The vulnerability in the Linux kernel's stratix10-rsu firmware driver arises from improper handling of timeout errors in rsu_send_msg(). When wait_for_completion_interruptible_timeout() triggers a timeout, certain error paths in stratix10_rsu_probe() call stratix10_svc_free_channel(), which sets chan->scl to NULL, but then continue to queue requests on the same channel. This leads to a NULL pointer dereference in the kernel thread's receive callback path. The patch applies a cleanup pattern to remove the async client, free the channel, and return early to avoid further queuing on cleared channels. Additional code cleanup improves resource unwinding and initialization ordering without changing behavior.

CWE-476NULL Pointer Dereference (opens in a new tab)
Base weaknessLikelihood of exploit: MediumCWE Top 25 (2025): #13OWASP Top 10 A10:2025: Mishandling of Exceptional Conditions (opens in a new tab)
The product dereferences a pointer that it expects to be valid but is NULL.
Implementation
For any pointers that could have been modified or provided from a function that can return NULL, check the pointer for NULL before use. When working with a multithreaded or otherwise asynchronous environment, ensure that proper locking APIs are used to lock before the check, and unlock when it has finished.
Requirements
Select a programming language that is not susceptible to these issues.
Implementation
Check the results of all functions that return a value and verify that the value is non-null before acting upon it.
OWASP Cheat Sheets
Logging (opens in a new tab)
Error Handling (opens in a new tab)
OWASP ASVS 4.0.3
V11.1.7 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Description

AI analysisMachine-generated, updated 2 Jul 2026, 23:03 UTC

WeaknessesCWE-476

Technical details

References

Community reviews

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