Description
A flaw has been found in davenardella snap7 up to 1.4.3. This affects the function TS7Worker::PerformFunctionRead of the file src/core/s7_server.cpp of the component ReadVar Request Handler. This manipulation causes out-of-bounds write. The attack requires access to the local network. The exploit has been published and may be used. The project was informed of the problem early through an issue report but has not responded yet.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| davenardella | snap7 | 1.4.0, 1.4.1, 1.4.2, 1.4.3 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | snap7 | No fix yet | — |
| Ubuntu 26.04 LTS | snap7 | No fix yet | — |
| Ubuntu 25.10 | snap7 | No fix yet | — |
References
- VDB-376946 | davenardella snap7 ReadVar Request s7_server.cpp PerformFunctionRead out-of-bounds write vdb-entry technical-description
- VDB-376946 | CTI Indicators (IOB, IOC, IOA) signature permissions-required
- CVE-2026-15105 | CVE Analysis and Report third-party-advisory
- Submit #851026 | Davide Nardella Snap7 master(commit:30f37da3114024a71ba93f7fd855c680b97a406f) Stack-based Buffer Overflow third-party-advisory
- https://github.com/davenardella/snap7/issues/16 issue-tracking
- https://github.com/user-attachments/files/28681740/poc.zip exploit
- https://github.com/davenardella/snap7/ product