Linux Kernel up to 6.6.127/6.12.74/6.18.13/6.19.3 rxe retransmit_timer use after free

| CVSS Meta Temp Score | Current Exploit Price (≈) | CTI Interest Score |
|---|---|---|
| 7.7 | $0-$5k | 0.00 |
Summary
A vulnerability was found in Linux Kernel up to 6.6.127/6.12.74/6.18.13/6.19.3 and classified as critical. Affected is the function retransmit_timer of the component rxe. The manipulation results in use after free.
This vulnerability is known as CVE-2026-45910. No exploit is available.
It is suggested to upgrade the affected component.
Details
A vulnerability was found in Linux Kernel up to 6.6.127/6.12.74/6.18.13/6.19.3. It has been classified as critical. Affected is the function retransmit_timer of the component rxe. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:
In the Linux kernel, the following vulnerability has been resolved: RDMA/rxe: Fix race condition in QP timer handlers I encontered the following warning: WARNING: drivers/infiniband/sw/rxe/rxe_task.c:249 at rxe_sched_task+0x1c8/0x238 [rdma_rxe], CPU#0: swapper/0/0 ... libsha1 [last unloaded: ip6_udp_tunnel] CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G C 6.19.0-rc5-64k-v8+ #37 PREEMPT Tainted: [C]=CRAP Hardware name: Raspberry Pi 4 Model B Rev 1.2 Call trace: rxe_sched_task+0x1c8/0x238 [rdma_rxe] (P) retransmit_timer+0x130/0x188 [rdma_rxe] call_timer_fn+0x68/0x4d0 __run_timers+0x630/0x888 ... WARNING: drivers/infiniband/sw/rxe/rxe_task.c:38 at rxe_sched_task+0x1c0/0x238 [rdma_rxe], CPU#0: swapper/0/0 ... WARNING: drivers/infiniband/sw/rxe/rxe_task.c:111 at do_work+0x488/0x5c8 [rdma_rxe], CPU#3: kworker/u17:4/93400 ... refcount_t: underflow; use-after-free. WARNING: lib/refcount.c:28 at refcount_warn_saturate+0x138/0x1a0, CPU#3: kworker/u17:4/93400 The issue is caused by a race condition between retransmit_timer() and rxe_destroy_qp, leading to the Queue Pair's (QP) reference count dropping to zero during timer handler execution. It seems this warning is harmless because rxe_qp_do_cleanup() will flush all pending timers and requests. Example of flow causing the issue: CPU0 CPU1 retransmit_timer() { spin_lock_irqsave rxe_destroy_qp() __rxe_cleanup() __rxe_put() // qp->ref_count decrease to 0 rxe_qp_do_cleanup() { if (qp->valid) { rxe_sched_task() { WARN_ON(rxe_read(task->qp) <= 0); } } spin_unlock_irqrestore } spin_lock_irqsave qp->valid = 0 spin_unlock_irqrestore } Ensure the QP's reference count is maintained and its validity is checked within the timer callbacks by adding calls to rxe_get(qp) and corresponding rxe_put(qp) after use.
The advisory is available at git.kernel.org. This vulnerability is traded as CVE-2026-45910 since 05/13/2026. The exploitability is told to be easy. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 06/24/2026).
The vulnerability scanner Nessus provides a plugin with the ID 321065 (SUSE SLES15 Security Update : kernel (SUSE-SU-2026:2310-1)), which helps to determine the existence of the flaw in a target environment.
Upgrading to version 6.6.128, 6.12.75, 6.18.14 or 6.19.4 eliminates this vulnerability. Applying the patch 756c93d6df7c3bc599f6590b8e5afead6a41de1c/3c2ae79fb19dfd67341c14f1e78a5f1744eacfe2/5ae9da022ee3c97e6469eabcddce9271501ddbad/da379ca16af3722f159860d91a99cb6976a7500f/87bf646921430e303176edc4eb07c30160361b73 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.
The vulnerability is also documented in the databases at Tenable (321065) and CERT Bund (WID-SEC-2026-1700). If you want to get best quality of vulnerability data, you may have to visit VulDB.
Affected
- Google Container-Optimized OS
- Debian Linux
- Red Hat Enterprise Linux
- Ubuntu Linux
- SUSE Linux
- Oracle Linux
- SUSE openSUSE
- RESF Rocky Linux
- Open Source Linux Kernel
Product
Type
Vendor
Name
Version
- 6.6.127
- 6.12.0
- 6.12.1
- 6.12.2
- 6.12.3
- 6.12.4
- 6.12.5
- 6.12.6
- 6.12.7
- 6.12.8
- 6.12.9
- 6.12.10
- 6.12.11
- 6.12.12
- 6.12.13
- 6.12.14
- 6.12.15
- 6.12.16
- 6.12.17
- 6.12.18
- 6.12.19
- 6.12.20
- 6.12.21
- 6.12.22
- 6.12.23
- 6.12.24
- 6.12.25
- 6.12.26
- 6.12.27
- 6.12.28
- 6.12.29
- 6.12.30
- 6.12.31
- 6.12.32
- 6.12.33
- 6.12.34
- 6.12.35
- 6.12.36
- 6.12.37
- 6.12.38
- 6.12.39
- 6.12.40
- 6.12.41
- 6.12.42
- 6.12.43
- 6.12.44
- 6.12.45
- 6.12.46
- 6.12.47
- 6.12.48
- 6.12.49
- 6.12.50
- 6.12.51
- 6.12.52
- 6.12.53
- 6.12.54
- 6.12.55
- 6.12.56
- 6.12.57
- 6.12.58
- 6.12.59
- 6.12.60
- 6.12.61
- 6.12.62
- 6.12.63
- 6.12.64
- 6.12.65
- 6.12.66
- 6.12.67
- 6.12.68
- 6.12.69
- 6.12.70
- 6.12.71
- 6.12.72
- 6.12.73
- 6.12.74
- 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
- 6.19.0
- 6.19.1
- 6.19.2
- 6.19.3
License
Website
- Vendor: https://www.kernel.org/
CPE 2.3
CPE 2.2
CVSSv4
VulDB Vector: 🔒VulDB Reliability: 🔍
CVSSv3
VulDB Meta Base Score: 7.9VulDB Meta Temp Score: 7.7
VulDB Base Score: 8.0
VulDB Temp Score: 7.6
VulDB Vector: 🔒
VulDB Reliability: 🔍
CNA Base Score: 7.8
CNA Vector (Linux): 🔒
CVSSv2
| AV | AC | Au | C | I | A |
|---|---|---|---|---|---|
| 💳 | 💳 | 💳 | 💳 | 💳 | 💳 |
| 💳 | 💳 | 💳 | 💳 | 💳 | 💳 |
| 💳 | 💳 | 💳 | 💳 | 💳 | 💳 |
| 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: Use after freeCWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒
Physical: Partially
Local: Yes
Remote: Partially
Availability: 🔒
Status: Not defined
EPSS Score: 🔒
EPSS Percentile: 🔒
Price Prediction: 🔍
Current Price Estimation: 🔒
| 0-Day | Unlock | Unlock | Unlock | Unlock |
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| Today | Unlock | Unlock | Unlock | Unlock |
Nessus ID: 321065
Nessus Name: SUSE SLES15 Security Update : kernel (SUSE-SU-2026:2310-1)
Threat Intelligence
Interest: 🔍Active Actors: 🔍
Active APT Groups: 🔍
Countermeasures
Recommended: UpgradeStatus: 🔍
0-Day Time: 🔒
Upgrade: Kernel 6.6.128/6.12.75/6.18.14/6.19.4
Patch: 756c93d6df7c3bc599f6590b8e5afead6a41de1c/3c2ae79fb19dfd67341c14f1e78a5f1744eacfe2/5ae9da022ee3c97e6469eabcddce9271501ddbad/da379ca16af3722f159860d91a99cb6976a7500f/87bf646921430e303176edc4eb07c30160361b73
Timeline
05/13/2026 CVE reserved05/27/2026 Advisory disclosed
05/27/2026 VulDB entry created
06/24/2026 VulDB entry last update
Sources
Vendor: kernel.orgAdvisory: git.kernel.org
Status: Confirmed
CVE: CVE-2026-45910 (🔒)
GCVE (CVE): GCVE-0-2026-45910
GCVE (VulDB): GCVE-100-366090
CERT Bund: WID-SEC-2026-1700 - Linux Kernel: Mehrere Schwachstellen
Entry
Created: 05/27/2026 16:25Updated: 06/24/2026 23:07
Changes: 05/27/2026 16:25 (59), 06/14/2026 23:51 (2), 06/15/2026 06:09 (7), 06/23/2026 03:01 (1), 06/24/2026 23:07 (11)
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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