Linux Kernel up to 6.12.110/6.18.52/7.2.6/7.3-rc2 USB Ethernet Driver rx_fixup len/partial_len/partial_rem heap-based overflow

| CVSS Meta Temp Score | Current Exploit Price (≈) | CTI Interest Score |
|---|---|---|
| 9.5 | $5k-$25k | 0.00+ |
Summary
A vulnerability was found in Linux Kernel up to 6.12.110/6.18.52/7.2.6/7.3-rc2. It has been rated as very critical. This issue affects the function rx_fixup of the component USB Ethernet Driver. The manipulation of the argument len/partial_len/partial_rem leads to heap-based overflow.
This vulnerability is traded as CVE-2026-98025. It is possible to initiate the attack remotely. There is no exploit available.
Upgrading the affected component is advised.
Details
A vulnerability, which was classified as very critical, has been found in Linux Kernel up to 6.12.110/6.18.52/7.2.6/7.3-rc2. This issue affects the function rx_fixup of the component USB Ethernet Driver. The manipulation of the argument len/partial_len/partial_rem with an unknown input leads to a heap-based overflow vulnerability. Using CWE to declare the problem leads to CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). Impacted is confidentiality, integrity, and availability. The summary by CVE is:
In the Linux kernel, the following vulnerability has been resolved: net: usb: cx82310_eth: drop URB after 0xffff reboot sentinel to prevent partial_data heap overflow The 0xffff length sentinel detects a router reboot and schedules re-enabling of ethernet mode, but then falls through to the rest of the loop body. The next check is } else if (len > CX82310_MTU) { which is the else of the just-matched if -- it never fires for len == 0xffff. The MTU bound that normally caps the incomplete-packet save path is silently bypassed. With 0xffff > skb->len always true (rx_urb_size is 4096), the incomplete-packet branch saves dev->partial_len = skb->len bytes into dev->partial_data. partial_data is kmalloc(hard_mtu) = kmalloc(CX82310_MTU + 2) = 1516 bytes, but skb->len after the 2-byte header pull can be up to 4094. A device that sends a 4096-byte URB starting with [0xff 0xff] therefore copies 4094 device-provided bytes into a buffer allocated for 1516 bytes, exceeding its requested size by 2578 bytes. The next URB then reads dev->partial_len (4094) back from the same 1516-byte buffer and dev->partial_rem (65535 - 4094 = 61441) from the new URB's ~4KB skb, both well past their allocations, and delivers the spliced result as a 64KB "frame" to the network stack. Bail out of rx_fixup after scheduling the re-enable work; the remainder of a reboot-marker URB is not meaningful packet data. This restores the invariant that partial_len < CX82310_MTU + 2 on the save path, since every other route there has already passed the MTU check.
The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2026-98025 since 09/25/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are known, but no exploit is available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 09/25/2026).
Upgrading to version 6.12.111, 6.18.53, 7.2.7 or 7.3-rc3 eliminates this vulnerability. Applying the patch 3bd689409bb1c93bdc6dd8ec6cbf5161bc4f0287/659654654eb140851467af41d610473c100c7975/237c9ae7145772af147e4665f158938350fa5658/5d50e90add8b4a978395e893e81954d19d58a7c5 is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Product
Type
Vendor
Name
Version
- 6.12.110
- 6.18.0
- 6.18.1
- 6.18.2
- 6.18.3
- 6.18.4
- 6.18.5
- 6.18.6
- 6.18.7
- 6.18.8
- 6.18.9
- 6.18.10
- 6.18.11
- 6.18.12
- 6.18.13
- 6.18.14
- 6.18.15
- 6.18.16
- 6.18.17
- 6.18.18
- 6.18.19
- 6.18.20
- 6.18.21
- 6.18.22
- 6.18.23
- 6.18.24
- 6.18.25
- 6.18.26
- 6.18.27
- 6.18.28
- 6.18.29
- 6.18.30
- 6.18.31
- 6.18.32
- 6.18.33
- 6.18.34
- 6.18.35
- 6.18.36
- 6.18.37
- 6.18.38
- 6.18.39
- 6.18.40
- 6.18.41
- 6.18.42
- 6.18.43
- 6.18.44
- 6.18.45
- 6.18.46
- 6.18.47
- 6.18.48
- 6.18.49
- 6.18.50
- 6.18.51
- 6.18.52
- 7.2.0
- 7.2.1
- 7.2.2
- 7.2.3
- 7.2.4
- 7.2.5
- 7.2.6
- 7.3-rc1
- 7.3-rc2
License
Website
- Vendor: https://www.kernel.org/
CPE 2.3
CPE 2.2
CVSSv4
VulDB Vector: 🔒VulDB Reliability: 🔍
CVSSv3
VulDB Meta Base Score: 10.0VulDB Meta Temp Score: 9.5
VulDB Base Score: 10.0
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍
CVSSv2
| AV | AC | Au | C | I | A |
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| 💳 | 💳 | 💳 | 💳 | 💳 | 💳 |
| 💳 | 💳 | 💳 | 💳 | 💳 | 💳 |
| 💳 | 💳 | 💳 | 💳 | 💳 | 💳 |
| Vector | Complexity | Authentication | Confidentiality | Integrity | Availability |
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| Unlock | Unlock | Unlock | Unlock | Unlock | Unlock |
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍
Exploiting
Class: Heap-based overflowCWE: CWE-122 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒
Physical: No
Local: No
Remote: Yes
Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒
| 0-Day | Unlock | Unlock | Unlock | Unlock |
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Threat Intelligence
Interest: 🔍Active Actors: 🔍
Active APT Groups: 🔍
Countermeasures
Recommended: UpgradeStatus: 🔍
0-Day Time: 🔒
Upgrade: Kernel 6.12.111/6.18.53/7.2.7/7.3-rc3
Patch: 3bd689409bb1c93bdc6dd8ec6cbf5161bc4f0287/659654654eb140851467af41d610473c100c7975/237c9ae7145772af147e4665f158938350fa5658/5d50e90add8b4a978395e893e81954d19d58a7c5
Timeline
09/25/2026 Advisory disclosed09/25/2026 CVE reserved
09/25/2026 VulDB entry created
09/25/2026 VulDB entry last update
Sources
Vendor: kernel.orgAdvisory: git.kernel.org
Status: Confirmed
CVE: CVE-2026-98025 (🔒)
GCVE (CVE): GCVE-0-2026-98025
GCVE (VulDB): GCVE-100-410249
Entry
Created: 09/25/2026 16:05Changes: 09/25/2026 16:05 (60)
Complete: 🔍
Cache ID: 216::103
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
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