davenardella snap7 up to 1.4.3 src/core/s7_peer.cpp NegotiatePDULength out-of-bounds write

CVSS Meta Temp Score
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CTI Interest Score
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5.7$0-$5k2.43

Summaryinfo

A vulnerability has been found in davenardella snap7 up to 1.4.3 and classified as critical. This affects the function TSnap7Peer::NegotiatePDULength of the file src/core/s7_peer.cpp. This manipulation of the argument PDULength causes out-of-bounds write. This vulnerability is tracked as CVE-2026-16225. The attack is possible to be carried out remotely. Moreover, an exploit is present.

Detailsinfo

A vulnerability has been found in davenardella snap7 up to 1.4.3 and classified as critical. Affected by this vulnerability is the function TSnap7Peer::NegotiatePDULength of the file src/core/s7_peer.cpp. The manipulation of the argument PDULength with an unknown input leads to a out-of-bounds write vulnerability. The CWE definition for the vulnerability is CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was disclosed by Chuan Wei (weicrsec) as 17 as not defined issue (GitHub). It is possible to read the advisory at github.com. The vendor was not involved in the public release. This vulnerability is known as CVE-2026-16225. The exploitation appears to be easy. The attack can be launched remotely. Technical details and also a public exploit are known.

A public exploit has been developed by Chuan Wei (weicrsec) in Python. It is possible to download the exploit at github.com. It is declared as proof-of-concept.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 5.7

VulDB Base Score: 6.3
VulDB Temp Score: 5.7
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: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Author: Chuan Wei (weicrsec)
Programming Language: 🔒
Download: 🔒
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

07/18/2026 Advisory disclosed
07/18/2026 +0 days VulDB entry created
07/18/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: 17
Researcher: Chuan Wei (weicrsec)
Status: Not defined

CVE: CVE-2026-16225 (🔒)
GCVE (CVE): GCVE-0-2026-16225
GCVE (VulDB): GCVE-100-380047
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 07/18/2026 14:34
Updated: 07/18/2026 15:57
Changes: 07/18/2026 14:34 (57), 07/18/2026 15:56 (3), 07/18/2026 15:57 (6)
Complete: 🔍
Submitter: VULL
Committer: VULL
Cache ID: 216::103

Submitinfo

Accepted

  • Submit #858228: Davide Nardella Snap7 1.4.3 Heap-Based Intra-Object Out-of-Bounds Write (by VULL)

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