Linux Kernel up to 7.2-rc2 xt_connmark connmark_tg_check shift_bits integer overflow

CVSS Meta Temp Score
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CTI Interest Score
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8.7$5k-$25k0.00-

Summaryinfo

A vulnerability was found in Linux Kernel up to 7.2-rc2. It has been declared as very critical. This affects the function connmark_tg_check of the component xt_connmark. The manipulation of the argument shift_bits results in integer overflow. This vulnerability is reported as CVE-2026-72347. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability classified as very critical has been found in Linux Kernel up to 7.2-rc2. Affected is the function connmark_tg_check of the component xt_connmark. The manipulation of the argument shift_bits with an unknown input leads to a integer overflow vulnerability. CWE is classifying the issue as 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. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_connmark: reject invalid shift parameters Revision 2 of the CONNMARK target accepts user-controlled shift parameters and applies them to 32-bit mark values in connmark_tg_shift(). A shift_bits value of 32 or more triggers an undefined-shift bug when the rule is evaluated. Invalid shift_dir values are also accepted and silently fall back to the left-shift path. Reject invalid revision-2 shift parameters in connmark_tg_check() so malformed rules fail at installation time, before they can reach the packet path.

The advisory is available at git.kernel.org. This vulnerability is traded as CVE-2026-72347 since 08/09/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. Additional levels of successful authentication are required for exploitation. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 08/15/2026).

Upgrading to version 5.15.212, 6.1.178, 6.6.145, 6.12.97, 6.18.40, 7.1.5 or 7.2-rc3 eliminates this vulnerability. Applying the patch d8ce63d928b457fba7ed1e302492dfd32293671c/9657bb11a6376ab0a79f05d433713d6944111e9d/8ace320ac4416f5e5fbcd065309fb2dfcce787b0/c3fa852d117b3fda72265e4230e3967db4a74fcf/4eef84b09a3836919360c4232b0f16651a155eec/230173cc6105bdfb2696d37e6e56687b003fbe63/1b47026fb4b35bac850ad6e8a4ad7fc018e09ebc is able to eliminate this problem.

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Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.1
VulDB Meta Temp Score: 8.7

VulDB Base Score: 9.1
VulDB Temp Score: 8.7
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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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: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.15.212/6.1.178/6.6.145/6.12.97/6.18.40/7.1.5/7.2-rc3
Patch: d8ce63d928b457fba7ed1e302492dfd32293671c/9657bb11a6376ab0a79f05d433713d6944111e9d/8ace320ac4416f5e5fbcd065309fb2dfcce787b0/c3fa852d117b3fda72265e4230e3967db4a74fcf/4eef84b09a3836919360c4232b0f16651a155eec/230173cc6105bdfb2696d37e6e56687b003fbe63/1b47026fb4b35bac850ad6e8a4ad7fc018e09ebc

Timelineinfo

08/09/2026 CVE reserved
08/15/2026 +6 days Advisory disclosed
08/15/2026 +0 days VulDB entry created
08/15/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-72347 (🔒)
GCVE (CVE): GCVE-0-2026-72347
GCVE (VulDB): GCVE-100-390942

Entryinfo

Created: 08/15/2026 16:30
Changes: 08/15/2026 16:30 (60)
Complete: 🔍
Cache ID: 216::103

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