Linux Kernel up to 7.2-rc1 sch_teql net/sched teql_master_xmit slaves use after free

| CVSS Meta Temp Score | Current Exploit Price (≈) | CTI Interest Score |
|---|---|---|
| 9.5 | $5k-$25k | 0.96 |
Summary
A vulnerability categorized as very critical has been discovered in Linux Kernel up to 7.2-rc1. This affects the function teql_master_xmit of the file net/sched of the component sch_teql. Executing a manipulation of the argument slaves can lead to use after free.
This vulnerability is handled as CVE-2026-72390. The attack can be executed remotely. There is not any exploit available.
Details
A vulnerability was found in Linux Kernel up to 7.2-rc1. It has been declared as very critical. This vulnerability affects the function teql_master_xmit of the file net/sched of the component sch_teql. The manipulation of the argument slaves with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:
In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_teql: Introduce slaves_lock to avoid race condition and UAF The teql master->slaves singly linked list is not protected against multiple writes. It can be mod'ed concurently from teql_master_xmit(), teql_dequeue(), teql_init() and teql_destroy() without holding any list lock or RCU protection. [email protected] has demonstrated that the qdisc is freed after an RCU grace period, but teql_master_xmit() running on another CPU can still hold a stale pointer into the list, resulting in a slab-use-after-free: BUG: KASAN: slab-use-after-free in teql_master_xmit+0xf0f/0x16b0 Read of size 8 at addr ffff888013fb0440 by task poc/332 Freed 512-byte region [ffff888013fb0400, ffff888013fb0600) (kmalloc-512) The fix? Add a per-master slaves_lock spinlock that serializes all mutations of master->slaves and the NEXT_SLAVE() links in teql_destroy() and teql_qdisc_init(). teql_master_xmit() also takes the same slaves_lock around those updates. Annotate master->slaves and the per-slave ->next pointer with __rcu and use the appropriate RCU accessors everywhere they are touched: rcu_assign_pointer() on the writer side (under slaves_lock), rcu_dereference_protected() for the writer-side loads (also under slaves_lock), rcu_dereference_bh() for the loads in teql_master_xmit() and rtnl_dereference() for the loads in teql_master_open()/teql_master_mtu(), which run under RTNL. Pair this with rcu_read_lock_bh()/rcu_read_unlock_bh() around the list traversal in teql_master_xmit(), so that readers either observe a fully linked list or are deferred until the in-flight mutation completes. The two early-return paths in teql_master_xmit() are updated to release the RCU-bh read-side critical section before returning, since leaving it held would disable BH on that CPU for good.
The advisory is available at git.kernel.org. This vulnerability was named CVE-2026-72390 since 08/09/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 08/15/2026).
Upgrading to version 6.1.178, 6.6.145, 6.12.97, 6.18.40, 7.1.5 or 7.2-rc2 eliminates this vulnerability. Applying the patch 03c67781254c574ae7fa75e881239a78473bdf42/735567bde7401f82b064f9f107b52ee1bf84ed8c/11402e6e18e96df615cbcc58157818dd604b23ff/9b7d05cbaa60108642402100efa6aa288dd33023/b26aa9d993537a4c3167d8ceead3b7c69c3a0aac/e5b811fe793166aecc59b085c1b7c31262ef2316 is able to eliminate this problem.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Product
Type
Vendor
Name
Version
- 6.1.177
- 6.6.144
- 6.12.0
- 6.12.1
- 6.12.2
- 6.12.3
- 6.12.4
- 6.12.5
- 6.12.6
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- 6.12.40
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- 6.12.42
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- 6.12.73
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- 6.12.75
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- 6.12.77
- 6.12.78
- 6.12.79
- 6.12.80
- 6.12.81
- 6.12.82
- 6.12.83
- 6.12.84
- 6.12.85
- 6.12.86
- 6.12.87
- 6.12.88
- 6.12.89
- 6.12.90
- 6.12.91
- 6.12.92
- 6.12.93
- 6.12.94
- 6.12.95
- 6.12.96
- 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
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- 6.18.13
- 6.18.14
- 6.18.15
- 6.18.16
- 6.18.17
- 6.18.18
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- 6.18.21
- 6.18.22
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- 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
- 7.1.0
- 7.1.1
- 7.1.2
- 7.1.3
- 7.1.4
- 7.2-rc1
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 |
|---|---|---|---|---|---|
| 💳 | 💳 | 💳 | 💳 | 💳 | 💳 |
| 💳 | 💳 | 💳 | 💳 | 💳 | 💳 |
| 💳 | 💳 | 💳 | 💳 | 💳 | 💳 |
| Vector | Complexity | Authentication | Confidentiality | Integrity | Availability |
|---|---|---|---|---|---|
| Unlock | Unlock | Unlock | Unlock | Unlock | Unlock |
| Unlock | Unlock | Unlock | Unlock | Unlock | Unlock |
| Unlock | Unlock | Unlock | Unlock | Unlock | Unlock |
VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍
Exploiting
Class: Use after freeCWE: CWE-416 / 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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| Today | Unlock | Unlock | Unlock | Unlock |
Threat Intelligence
Interest: 🔍Active Actors: 🔍
Active APT Groups: 🔍
Countermeasures
Recommended: UpgradeStatus: 🔍
0-Day Time: 🔒
Upgrade: Kernel 6.1.178/6.6.145/6.12.97/6.18.40/7.1.5/7.2-rc2
Patch: 03c67781254c574ae7fa75e881239a78473bdf42/735567bde7401f82b064f9f107b52ee1bf84ed8c/11402e6e18e96df615cbcc58157818dd604b23ff/9b7d05cbaa60108642402100efa6aa288dd33023/b26aa9d993537a4c3167d8ceead3b7c69c3a0aac/e5b811fe793166aecc59b085c1b7c31262ef2316
Timeline
08/09/2026 CVE reserved08/15/2026 Advisory disclosed
08/15/2026 VulDB entry created
08/15/2026 VulDB entry last update
Sources
Vendor: kernel.orgAdvisory: git.kernel.org
Status: Confirmed
CVE: CVE-2026-72390 (🔒)
GCVE (CVE): GCVE-0-2026-72390
GCVE (VulDB): GCVE-100-390706
Entry
Created: 08/15/2026 14:12Changes: 08/15/2026 14:12 (61)
Complete: 🔍
Cache ID: 216::103
If you want to get best quality of vulnerability data, you may have to visit VulDB.
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