Linux Kernel up to 6.15.2 lib/iov_iter.c netfs_retry_write_stream out-of-bounds

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CTI Interest Score
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4.8$0-$5k2.13

Summaryinfo

A vulnerability, which was classified as problematic, has been found in Linux Kernel up to 6.15.2. This affects the function netfs_retry_write_stream in the library lib/iov_iter.c. This manipulation causes out-of-bounds. This vulnerability is tracked as CVE-2025-38139. No exploit exists. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.15.2 and classified as problematic. Affected by this vulnerability is the function netfs_retry_write_stream in the library lib/iov_iter.c. The manipulation with an unknown input leads to a out-of-bounds vulnerability. The CWE definition for the vulnerability is CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: netfs: Fix oops in write-retry from mis-resetting the subreq iterator Fix the resetting of the subrequest iterator in netfs_retry_write_stream() to use the iterator-reset function as the iterator may have been shortened by a previous retry. In such a case, the amount of data to be written by the subrequest is not "subreq->len" but "subreq->len - subreq->transferred". Without this, KASAN may see an error in iov_iter_revert(): BUG: KASAN: slab-out-of-bounds in iov_iter_revert lib/iov_iter.c:633 [inline] BUG: KASAN: slab-out-of-bounds in iov_iter_revert+0x443/0x5a0 lib/iov_iter.c:611 Read of size 4 at addr ffff88802912a0b8 by task kworker/u32:7/1147 CPU: 1 UID: 0 PID: 1147 Comm: kworker/u32:7 Not tainted 6.15.0-rc6-syzkaller-00052-g9f35e33144ae #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Workqueue: events_unbound netfs_write_collection_worker Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xc3/0x670 mm/kasan/report.c:521 kasan_report+0xe0/0x110 mm/kasan/report.c:634 iov_iter_revert lib/iov_iter.c:633 [inline] iov_iter_revert+0x443/0x5a0 lib/iov_iter.c:611 netfs_retry_write_stream fs/netfs/write_retry.c:44 [inline] netfs_retry_writes+0x166d/0x1a50 fs/netfs/write_retry.c:231 netfs_collect_write_results fs/netfs/write_collect.c:352 [inline] netfs_write_collection_worker+0x23fd/0x3830 fs/netfs/write_collect.c:374 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 </TASK>

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2025-38139 since 04/16/2025. The exploitation appears to be difficult. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 265934 (Ubuntu 24.04 LTS / 25.04 : Linux kernel vulnerabilities (USN-7769-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.15.3 or 6.16-rc1 eliminates this vulnerability. Applying the patch bd0edaf99a920b1a9decd773179caacacb61d0fd/4481f7f2b3df123ec77e828c849138f75cff2bf2 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 (265934), EUVD (EUVD-2025-19804) and CERT Bund (WID-SEC-2025-1452). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

  • Google Container-Optimized OS
  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • IBM QRadar SIEM
  • SUSE openSUSE
  • RESF Rocky Linux
  • Dell Avamar
  • Open Source Linux Kernel
  • Dell NetWorker
  • Dell Secure Connect Gateway

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.8
VulDB Meta Temp Score: 4.8

VulDB Base Score: 2.6
VulDB Temp Score: 2.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.1
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 265934
Nessus Name: Ubuntu 24.04 LTS / 25.04 : Linux kernel vulnerabilities (USN-7769-1)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.15.3/6.16-rc1
Patch: bd0edaf99a920b1a9decd773179caacacb61d0fd/4481f7f2b3df123ec77e828c849138f75cff2bf2

Timelineinfo

04/16/2025 CVE reserved
07/03/2025 +78 days Advisory disclosed
07/03/2025 +0 days VulDB entry created
04/18/2026 +289 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-38139 (🔒)
GCVE (CVE): GCVE-0-2025-38139
GCVE (VulDB): GCVE-100-314707
EUVD: 🔒
CERT Bund: WID-SEC-2025-1452 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 07/03/2025 12:05
Updated: 04/18/2026 05:46
Changes: 07/03/2025 12:05 (59), 07/03/2025 14:04 (1), 08/23/2025 19:11 (7), 09/21/2025 19:51 (1), 09/28/2025 00:44 (2), 11/09/2025 14:48 (1), 11/21/2025 03:12 (13), 12/06/2025 16:43 (1), 04/18/2026 05:46 (1)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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