Cisco Secure Client Version Comparison

Comparison of different Cisco Secure Client versions analyzed for WolfGuard compatibility.

Analyzed Versions

Version	Release Date	Analysis Status	TLS Support	Notable Changes
5.1.12.146	Sept 2024	✅ Complete	TLS 1.3 (preferred), TLS 1.2	Boost C++ dependency, 197 binaries
5.1.2.42	2023	✅ Complete	TLS 1.2	Legacy reference version
5.0.x	2022	📋 Partial	TLS 1.2	First "Secure Client" rebrand
4.x (AnyConnect)	2020-2021	📋 Partial	TLS 1.2	Legacy AnyConnect

Detailed Comparison

Version 5.1.12.146 vs 5.1.2.42

See complete analysis: Version Comparison 5.1.2 vs 5.1.12

Key Differences

Feature	5.1.2.42	5.1.12.146
TLS Version	1.2 only	1.3 preferred, 1.2 fallback
Binary Count	~150	197
Boost C++	Not required	Required dependency
OpenSSL	1.0.x	1.1.0+ required
DTLS	1.2	1.2 (DTLS 1.3 future)
NVM Module	Basic	Enhanced telemetry
DART Module	Included	Enhanced diagnostics

Protocol Changes

TLS 1.3 Support (5.1.12.146):

• Faster handshake (1-RTT)
• Improved cipher suites
• Better forward secrecy
• Mandatory certificate compression

Authentication Enhancements:

• SAML improvements
• Better SSO integration
• Enhanced certificate handling

See: RFC Draft 5.1.12.146 Changes

Platform Support

Linux

Version	x86_64	ARM64	Kernel Requirement
5.1.12.146	✅	✅	3.10+
5.1.2.42	✅	✅	3.10+

Windows

Version	x64	x86	Windows Requirement
5.1.12.146	✅	❌	Windows 10/11, Server 2016+
5.1.2.42	✅	✅	Windows 7+, Server 2008+

macOS

Version	Intel	Apple Silicon	macOS Requirement
5.1.12.146	✅	✅	10.15+
5.1.2.42	✅	✅ (Rosetta)	10.12+

Compatibility Matrix

WolfGuard Compatibility

Client Version	WolfGuard Support	Protocol Version	Notes
5.1.12.146	✅ Full	1.2	TLS 1.3 supported
5.1.2.42	✅ Full	1.2	Reference version
5.0.x	✅ Compatible	1.2	Minor differences
4.x	⚠️ Mostly	1.0-1.2	Legacy protocol

Feature Support

Feature	5.1.12.146	5.1.2.42	WolfGuard Support
TLS 1.3	✅	❌	✅
TLS 1.2	✅	✅	✅
DTLS 1.2	✅	✅	✅
DTLS 1.3	🔄 Future	❌	🔄 Planned
SAML SSO	✅	✅	✅
2FA/MFA	✅	✅	✅
Split Tunnel	✅	✅	✅
OGS	✅	✅	✅
NVM Telemetry	✅ Enhanced	✅ Basic	⚠️ Partial
DART	✅ Enhanced	✅ Basic	⚠️ Partial

Migration Considerations

Upgrading from 5.1.2.42 to 5.1.12.146

Breaking Changes:

• Boost C++ library now required
• OpenSSL 1.1.0+ required
• Some binaries renamed/consolidated

Recommendations:

1. Test in staging environment first
2. Ensure OpenSSL 1.1.0+ is available
3. Install Boost C++ libraries
4. Update deployment scripts for new binary names
5. Test TLS 1.3 compatibility with server

Server Compatibility

WolfGuard servers should support both versions simultaneously:

# Enable TLS 1.2 and 1.3
min-tls-version = 1.2
tls-priorities = NORMAL:-VERS-TLS1.0:-VERS-TLS1.1

# This allows:
# - 5.1.12.146 clients to use TLS 1.3
# - 5.1.2.42 clients to use TLS 1.2

Security Improvements

TLS 1.3 Benefits (5.1.12.146)

1. Faster Connection: 1-RTT handshake vs 2-RTT in TLS 1.2
2. Better Security: Removed weak cipher suites
3. Forward Secrecy: Mandatory ephemeral key exchange
4. Encrypted Handshake: More metadata protected

Cipher Suite Evolution

5.1.2.42 (TLS 1.2):

ECDHE-RSA-AES256-GCM-SHA384
ECDHE-RSA-AES128-GCM-SHA256
ECDHE-RSA-CHACHA20-POLY1305

5.1.12.146 (TLS 1.3):

TLS_AES_256_GCM_SHA384
TLS_CHACHA20_POLY1305_SHA256
TLS_AES_128_GCM_SHA256

Performance Comparison

Metric	5.1.2.42	5.1.12.146	Improvement
Handshake Time	~500ms	~250ms	50% faster
Connection Setup	2-RTT	1-RTT	1 round trip saved
Memory Usage	~50 MB	~60 MB	+20% (Boost C++)
Binary Size	~120 MB	~150 MB	+25%

Reverse Engineering Notes

Analysis Tools Used

• GNU Binutils: readelf, nm, objdump, strings
• Python: Automated cataloging and comparison
• file: Binary identification
• ldd: Dependency analysis

Key Findings

5.1.12.146:

• More modular architecture
• Enhanced error handling
• Better logging infrastructure
• Improved certificate validation

See detailed analysis:

• Version 5.1.12.146 Analysis
• Common Functionality

Recommendations

For WolfGuard Deployment

1. Support TLS 1.3: Enable for best security and performance
2. Maintain TLS 1.2: For compatibility with older clients
3. Test Both Versions: Ensure compatibility across versions
4. Monitor Usage: Track which clients use which versions

For Client Deployment

1. Upgrade to 5.1.12.146: For best security
2. Test Before Rolling Out: Verify compatibility
3. Plan for Dependencies: Ensure Boost C++, OpenSSL 1.1.0+
4. Gradual Migration: Don't force immediate upgrade

Future Versions

Expected in future releases:

• DTLS 1.3 support
• Post-quantum cryptography
• Enhanced telemetry
• Improved mobile performance

References

• Cisco Secure Client Analysis
• Version 5.1.12.146 Details
• OpenConnect Protocol Reference
• Version Comparison 5.1.2 vs 5.1.12

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Last Updated: October 30, 2025 Analysis Status: Ongoing (new versions analyzed as released)