Linux Kernel up to 6.6.140/6.12.90/6.18.32/7.0.9 netfilter nfnetlink_osf.c nf_osf_match_one divide by zero

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.
5.0$0-$5k0.00

Summaryinfo

A vulnerability described as critical has been identified in Linux Kernel up to 6.6.140/6.12.90/6.18.32/7.0.9. This impacts the function nf_osf_match_one of the file net/netfilter/nfnetlink_osf.c of the component netfilter. Such manipulation leads to divide by zero. This vulnerability is documented as CVE-2026-45841. There is not any exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.6.140/6.12.90/6.18.32/7.0.9. It has been rated as critical. Affected by this issue is the function nf_osf_match_one of the file net/netfilter/nfnetlink_osf.c of the component netfilter. The manipulation with an unknown input leads to a divide by zero vulnerability. Using CWE to declare the problem leads to CWE-369. The product divides a value by zero. Impacted is availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: netfilter: nfnetlink_osf: fix divide-by-zero in OSF_WSS_MODULO nf_osf_match_one() computes ctx->window % f->wss.val in the OSF_WSS_MODULO branch with no guard for f->wss.val == 0. A CAP_NET_ADMIN user can add such a fingerprint via nfnetlink; a subsequent matching TCP SYN divides by zero and panics the kernel. Reject the bogus fingerprint in nfnl_osf_add_callback() above the per-option for-loop. f->wss is per-fingerprint, not per-option, so the check must run regardless of f->opt_num (including 0). Also reject wss.wc >= OSF_WSS_MAX; nf_osf_match_one() already treats that as "should not happen". Crash: Oops: divide error: 0000 [#1] SMP KASAN NOPTI RIP: 0010:nf_osf_match_one (net/netfilter/nfnetlink_osf.c:98) Call Trace: <IRQ> nf_osf_match (net/netfilter/nfnetlink_osf.c:220) xt_osf_match_packet (net/netfilter/xt_osf.c:32) ipt_do_table (net/ipv4/netfilter/ip_tables.c:348) nf_hook_slow (net/netfilter/core.c:622) ip_local_deliver (net/ipv4/ip_input.c:265) ip_rcv (include/linux/skbuff.h:1162) __netif_receive_skb_one_core (net/core/dev.c:6181) process_backlog (net/core/dev.c:6642) __napi_poll (net/core/dev.c:7710) net_rx_action (net/core/dev.c:7945) handle_softirqs (kernel/softirq.c:622)

The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2026-45841 since 05/13/2026. The exploitation is known to be difficult. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 321868 (Debian dsa-6355 : ata-modules-6.12.90+deb13-armmp-di - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.6.141, 6.12.91, 6.18.33, 7.0.10 or 7.1-rc1 eliminates this vulnerability. Applying the patch 8def8fbd23f40e945febe913d04b731012ce0082/c55940895245d8ef658ab381248a28755218d625/fb965b1cfe92b28d28b5ebe3116b81dbef9f2d2f/9a05e195618a6d474f2bcd5b6376d0ffc2f00366/2195574dc6d9017d32ac346987e12659f931d932 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 (321868), EUVD (EUVD-2026-32167) and CERT Bund (WID-SEC-2026-1691). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Debian Linux
  • Amazon Linux 2
  • SUSE Linux
  • SUSE openSUSE
  • Open Source Linux Kernel
  • Ubuntu Linux

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.1
VulDB Meta Temp Score: 5.0

VulDB Base Score: 4.8
VulDB Temp Score: 4.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔒

CVSSv2info

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

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

Exploitinginfo

Class: Divide by zero
CWE: CWE-369 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Nessus ID: 321868
Nessus Name: Debian dsa-6355 : ata-modules-6.12.90+deb13-armmp-di - security update

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.6.141/6.12.91/6.18.33/7.0.10/7.1-rc1
Patch: 8def8fbd23f40e945febe913d04b731012ce0082/c55940895245d8ef658ab381248a28755218d625/fb965b1cfe92b28d28b5ebe3116b81dbef9f2d2f/9a05e195618a6d474f2bcd5b6376d0ffc2f00366/2195574dc6d9017d32ac346987e12659f931d932

Timelineinfo

05/13/2026 CVE reserved
05/27/2026 +14 days Advisory disclosed
05/27/2026 +0 days VulDB entry created
07/22/2026 +56 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-45841 (🔒)
GCVE (CVE): GCVE-0-2026-45841
GCVE (VulDB): GCVE-100-366056
EUVD: 🔒
CERT Bund: WID-SEC-2026-1691 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 05/27/2026 13:47
Updated: 07/22/2026 13:32
Changes: 05/27/2026 13:47 (60), 05/27/2026 15:53 (7), 05/27/2026 16:01 (1), 06/15/2026 12:29 (1), 06/21/2026 22:06 (2), 06/26/2026 21:05 (12), 07/22/2026 13:32 (1)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Might our Artificial Intelligence support you?

Check our Alexa App!