Linux Kernel up to 7.2-rc4 binfmt_flat/binfmt_elf_fdpic fs/exec.c transfer_args_to_stack buffer overflow

| CVSS Meta Temp Score | Current Exploit Price (≈) | CTI Interest Score |
|---|---|---|
| 8.4 | $0-$5k | 0.00 |
Summary
A vulnerability, which was classified as very critical, was found in Linux Kernel up to 6.6.147/6.12.100/6.18.41/7.1.5/7.2-rc4. This impacts the function transfer_args_to_stack of the file fs/exec.c of the component binfmt_flat/binfmt_elf_fdpic. Executing a manipulation of the argument p can lead to buffer overflow.
This vulnerability is registered as CVE-2026-68187. The attack needs to be launched locally. No exploit is available.
Details
A vulnerability classified as very critical was found in Linux Kernel up to 6.6.147/6.12.100/6.18.41/7.1.5/7.2-rc4. This vulnerability affects the function transfer_args_to_stack of the file fs/exec.c of the component binfmt_flat/binfmt_elf_fdpic. The manipulation of the argument p with an unknown input leads to a buffer overflow vulnerability. The CWE definition for the vulnerability is CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:
In the Linux kernel, the following vulnerability has been resolved: exec: fix unsigned loop counter wrap in transfer_args_to_stack() The stop value is derived from bprm->p >> PAGE_SHIFT. The index variable is an unsigned long. If bprm->p drops below PAGE_SIZE and stop becomes zero the loop condition index >= stop is always true. After the index == 0 iteration the decrement wraps to ULONG_MAX and bprm->page[ULONG_MAX] reads sizeof(void *) bytes in front of the array. The pointer has wrapped to -1. That garbage pointer is then passed to kmap_local_page() and PAGE_SIZE bytes are copied from wherever that lands into the stack of the process being created. And the loop doesn't terminate either... Getting there only requires bprm->p < PAGE_SIZE. On !MMU bprm_set_stack_limit() and bprm_hit_stack_limit() are empty. So the only constraint on how far bprm->p is pushed down is valid_arg_len(), i.e. that each individual string still fits in what is left. bprm->p starts at PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *) so a single argument or environment string of a little over 31 pages leaves it in the first page: Oops - load access fault [#1] CPU: 0 UID: 0 PID: 1 Comm: victim Not tainted 7.2.0-rc4 #1 epc : __memcpy+0xd4/0xf8 ra : transfer_args_to_stack+0xaa/0xae s4 : ffffffffffffffff s2 : 0000000000000000 a1 : ffffffdc98000000 a2 : 0000000000001000 status: 0000000a00001880 badaddr: ffffffdc98000000 cause: 0000000000000005 [<801a5324>] __memcpy+0xd4/0xf8 [<800d5f6a>] load_flat_binary+0x43a/0x65e [<800a2de4>] bprm_execve+0x1d4/0x316 [<800a351a>] do_execveat_common+0x12e/0x138 [<800a3d44>] __riscv_sys_execve+0x38/0x4e Kernel panic - not syncing: Fatal exception in interrupt This is an arcane bug but we should still fix it. Count down from MAX_ARG_PAGES so the loop ends when index reaches stop, stop == 0 included. The iterations performed are unchanged for every other value of stop. Only CONFIG_MMU=n builds are affected, transfer_args_to_stack() is used by binfmt_flat and binfmt_elf_fdpic on nommu only. The loop predates git history. commit 7e7ec6a93434 ("elf_fdpic_transfer_args_to_stack(): make it generic") only moved it from binfmt_elf_fdpic.c into fs/exec.c and narrowed the copy to the used part of the first page. The condition and the decrement are unchanged from 2.6.12-rc2.
The advisory is available at git.kernel.org. This vulnerability was named CVE-2026-68187 since 07/30/2026. The exploitation appears to be easy. Local access is required to approach this attack. 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 08/10/2026).
Upgrading to version 6.6.148, 6.12.101, 6.18.42, 7.1.6 or 7.2-rc5 eliminates this vulnerability. Applying the patch c62bb00caba66e01fb578d5f0302f247dc64930a/dfc2a00742af4cb7251c1a8fbce4fbae3cc0de4e/2bc6bf70d41055377f390d06f0f3521deb62fd3b/55fa2c7f2b15583d1a2fe1b5abcc24377359339f/16cc4f5c1c4b9e45eca7f7deefa5410a292db599 is able to eliminate this problem.
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Product
Type
Vendor
Name
Version
- 6.0
- 6.1
- 6.2
- 6.3
- 6.4
- 6.5
- 6.6
- 6.6.147
- 6.7
- 6.8
- 6.9
- 6.10
- 6.11
- 6.12.100
- 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
- 7.1.0
- 7.1.1
- 7.1.2
- 7.1.3
- 7.1.4
- 7.1.5
- 7.2-rc1
- 7.2-rc2
- 7.2-rc3
- 7.2-rc4
License
Website
- Vendor: https://www.kernel.org/
CPE 2.3
CPE 2.2
CVSSv4
VulDB Vector: 🔒VulDB Reliability: 🔍
CVSSv3
VulDB Meta Base Score: 8.8VulDB Meta Temp Score: 8.4
VulDB Base Score: 8.8
VulDB Temp Score: 8.4
VulDB Vector: 🔒
VulDB Reliability: 🔍
CVSSv2
| AV | AC | Au | C | I | A |
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| 💳 | 💳 | 💳 | 💳 | 💳 | 💳 |
| 💳 | 💳 | 💳 | 💳 | 💳 | 💳 |
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| Vector | Complexity | Authentication | Confidentiality | Integrity | Availability |
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍
Exploiting
Class: Buffer overflowCWE: CWE-120 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒
Physical: Partially
Local: Yes
Remote: No
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 6.6.148/6.12.101/6.18.42/7.1.6/7.2-rc5
Patch: c62bb00caba66e01fb578d5f0302f247dc64930a/dfc2a00742af4cb7251c1a8fbce4fbae3cc0de4e/2bc6bf70d41055377f390d06f0f3521deb62fd3b/55fa2c7f2b15583d1a2fe1b5abcc24377359339f/16cc4f5c1c4b9e45eca7f7deefa5410a292db599
Timeline
07/30/2026 CVE reserved08/10/2026 Advisory disclosed
08/10/2026 VulDB entry created
08/10/2026 VulDB entry last update
Sources
Vendor: kernel.orgAdvisory: git.kernel.org
Status: Confirmed
CVE: CVE-2026-68187 (🔒)
GCVE (CVE): GCVE-0-2026-68187
GCVE (VulDB): GCVE-100-387550
Entry
Created: 08/10/2026 16:02Changes: 08/10/2026 16:02 (61)
Complete: 🔍
Cache ID: 216::103
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