PolarProxyMalware AnalysisC2TLSComparisonAlternatives
PolarProxy vs InterceptSuite: Decrypt-Only vs Decrypt-and-Edit
PolarProxy decrypts TLS to PCAP for analysis. InterceptSuite also lets you edit and replay C2 traffic in a lab. A fair comparison for malware analysts and DFIR teams.
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InterceptSuite Team
October 6, 2026·5 min read
Short answer: PolarProxy, from Netresec, is a transparent TLS proxy that decrypts traffic and writes it to PCAP so you can analyse it in Wireshark. It is passive. InterceptSuite also decrypts, but lets you hold, edit and replay the packets, and covers DTLS, QUIC, UDP and STARTTLS. Pick PolarProxy to record and analyse. Pick InterceptSuite to change what the sample sees and sends.
Last updated 6 October 2026.
Side by side
| PolarProxy | InterceptSuite | |
|---|---|---|
| Purpose | Decrypt TLS to PCAP | Intercept, edit and replay non-HTTP traffic |
| Edit or hold packets | No, passive decrypt and forward | Yes, with rules per direction and a hex editor |
| Resend packets | No | Replay over TCP, TLS, UDP, DTLS, QUIC and STARTTLS |
| Protocols | Any TLS-based protocol (HTTPS, SMTPS, IMAPS and others) | TCP, TLS, DTLS, QUIC v1, UDP and STARTTLS |
| STARTTLS | Its 0.9 notes say explicit TLS that relies on opportunistic upgrades such as STARTTLS is not supported | Upgrade detection built in |
| Interface | Command line, output to PCAP | Native desktop GUI |
| Price | Free up to 10 GB or 10,000 TLS sessions per day, paid tiers above that; free licences for vetted researchers | Paid, 7-day trial |
Where PolarProxy is the better choice
- Passive capture at scale. If your goal is a decrypted PCAP of a sample's traffic for Wireshark, Arkime or Zeek, PolarProxy does exactly that.
- Cost. The free tier is generous, and Netresec offers licences to vetted malware analysts.
- Established lab guides. Many sandbox walkthroughs already use it.
Where InterceptSuite adds value for C2 analysis
- Change the conversation. Edit a C2 command in flight, drop a beacon, or alter a server reply to see how the sample reacts.
- Replay commands. Send a captured command again from Replay and read the response, to test handling without the original server.
- More than TLS over TCP. Malware that uses DTLS, QUIC or raw UDP is covered in the same tool.
- Mixed and STARTTLS channels. Plaintext-then-TLS protocols are detected automatically.
For a full lab walkthrough, read Decrypt and Modify Malware C2 TLS Traffic.
A sensible setup
Many analysts use both: PolarProxy for passive recording, InterceptSuite when they need to interact. InterceptSuite exports PCAP too, so captures still open in Wireshark.
Limits to know
InterceptSuite cannot decrypt connections that use Encrypted Client Hello (ECH), and QUIC v2 and DTLS 1.3 are not supported yet. Use it only on systems and samples you are authorised to analyse, in an isolated lab.
Start the 7-day trial to try it against your own sample.