Linux Kernel up to 6.19.8 integer overflow

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.7$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.19.8. Affected by this issue is some unknown functionality. The manipulation leads to integer overflow. This vulnerability is referenced as CVE-2026-43407. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.19.8 and classified as critical. This issue affects some unknown processing. The manipulation with an unknown input leads to a integer overflow vulnerability. Using CWE to declare the problem leads to CWE-190. The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control. The impact remains unknown. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: libceph: Fix potential out-of-bounds access in ceph_handle_auth_reply() This patch fixes an out-of-bounds access in ceph_handle_auth_reply() that can be triggered by a message of type CEPH_MSG_AUTH_REPLY. In ceph_handle_auth_reply(), the value of the payload_len field of such a message is stored in a variable of type int. A value greater than INT_MAX leads to an integer overflow and is interpreted as a negative value. This leads to decrementing the pointer address by this value and subsequently accessing it because ceph_decode_need() only checks that the memory access does not exceed the end address of the allocation. This patch fixes the issue by changing the data type of payload_len to u32. Additionally, the data type of result_msg_len is changed to u32, as it is also a variable holding a non-negative length. Also, an additional layer of sanity checks is introduced, ensuring that directly after reading it from the message, payload_len and result_msg_len are not greater than the overall segment length. BUG: KASAN: slab-out-of-bounds in ceph_handle_auth_reply+0x642/0x7a0 [libceph] Read of size 4 at addr ffff88811404df14 by task kworker/20:1/262 CPU: 20 UID: 0 PID: 262 Comm: kworker/20:1 Not tainted 6.19.2 #5 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Workqueue: ceph-msgr ceph_con_workfn [libceph] Call Trace: <TASK> dump_stack_lvl+0x76/0xa0 print_report+0xd1/0x620 ? __pfx__raw_spin_lock_irqsave+0x10/0x10 ? kasan_complete_mode_report_info+0x72/0x210 kasan_report+0xe7/0x130 ? ceph_handle_auth_reply+0x642/0x7a0 [libceph] ? ceph_handle_auth_reply+0x642/0x7a0 [libceph] __asan_report_load_n_noabort+0xf/0x20 ceph_handle_auth_reply+0x642/0x7a0 [libceph] mon_dispatch+0x973/0x23d0 [libceph] ? apparmor_socket_recvmsg+0x6b/0xa0 ? __pfx_mon_dispatch+0x10/0x10 [libceph] ? __kasan_check_write+0x14/0x30i ? mutex_unlock+0x7f/0xd0 ? __pfx_mutex_unlock+0x10/0x10 ? __pfx_do_recvmsg+0x10/0x10 [libceph] ceph_con_process_message+0x1f1/0x650 [libceph] process_message+0x1e/0x450 [libceph] ceph_con_v2_try_read+0x2e48/0x6c80 [libceph] ? __pfx_ceph_con_v2_try_read+0x10/0x10 [libceph] ? save_fpregs_to_fpstate+0xb0/0x230 ? raw_spin_rq_unlock+0x17/0xa0 ? finish_task_switch.isra.0+0x13b/0x760 ? __switch_to+0x385/0xda0 ? __kasan_check_write+0x14/0x30 ? mutex_lock+0x8d/0xe0 ? __pfx_mutex_lock+0x10/0x10 ceph_con_workfn+0x248/0x10c0 [libceph] process_one_work+0x629/0xf80 ? __kasan_check_write+0x14/0x30 worker_thread+0x87f/0x1570 ? __pfx__raw_spin_lock_irqsave+0x10/0x10 ? __pfx_try_to_wake_up+0x10/0x10 ? kasan_print_address_stack_frame+0x1f7/0x280 ? __pfx_worker_thread+0x10/0x10 kthread+0x396/0x830 ? __pfx__raw_spin_lock_irq+0x10/0x10 ? __pfx_kthread+0x10/0x10 ? __kasan_check_write+0x14/0x30 ? recalc_sigpending+0x180/0x210 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x3f7/0x610 ? __pfx_ret_from_fork+0x10/0x10 ? __switch_to+0x385/0xda0 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> [ idryomov: replace if statements with ceph_decode_need() for payload_len and result_msg_len ]

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2026-43407 since 05/01/2026. The exploitation is known to be difficult. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 05/22/2026).

The vulnerability scanner Nessus provides a plugin with the ID 313397 (Linux Distros Unpatched Vulnerability : CVE-2026-43407), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.10.253, 5.15.203, 6.1.167, 6.6.130, 6.12.78, 6.18.19 or 6.19.9 eliminates this vulnerability. Applying the patch ea080b21092590122c3f971cf588932cdbf47847/edc678e5cd11730a2834b43071d8923f05bc334d/6cee34d6669fe176b4259131adb1a145c939b472/8bb87547e92dcf0928ed763c60e0ac8d733c3656/ed024d2f4c79c0eb2464df0fb640610ac301f9a0/f9da5c1bbac5c8e33259fe00ed7347438fffa969/9f9e2297f45fc2d2524eb104c289d69ddef95665/b282c43ed156ae15ea76748fc15cd5c39dc9ab72 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 vulnerability database at Tenable (313397). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.8
VulDB Meta Temp Score: 6.7

VulDB Base Score: 4.6
VulDB Temp Score: 4.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 9.1
CNA Vector (Linux): 🔒

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Integer overflow
CWE: CWE-190 / CWE-189
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Nessus ID: 313397
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-43407

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.10.253/5.15.203/6.1.167/6.6.130/6.12.78/6.18.19/6.19.9
Patch: ea080b21092590122c3f971cf588932cdbf47847/edc678e5cd11730a2834b43071d8923f05bc334d/6cee34d6669fe176b4259131adb1a145c939b472/8bb87547e92dcf0928ed763c60e0ac8d733c3656/ed024d2f4c79c0eb2464df0fb640610ac301f9a0/f9da5c1bbac5c8e33259fe00ed7347438fffa969/9f9e2297f45fc2d2524eb104c289d69ddef95665/b282c43ed156ae15ea76748fc15cd5c39dc9ab72

Timelineinfo

05/01/2026 CVE reserved
05/08/2026 +7 days Advisory disclosed
05/08/2026 +0 days VulDB entry created
05/22/2026 +13 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-43407 (🔒)
GCVE (CVE): GCVE-0-2026-43407
GCVE (VulDB): GCVE-100-362165

Entryinfo

Created: 05/08/2026 18:15
Updated: 05/22/2026 01:37
Changes: 05/08/2026 18:15 (57), 05/09/2026 07:32 (2), 05/22/2026 01:37 (12)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Want to stay up to date on a daily basis?

Enable the mail alert feature now!