IPsec implementation flaw attacks¶

Attack pattern¶

Strong algorithms do not save a weak implementation. The library that runs the crypto, the code that gathers randomness, the daemon that parses IKE packets, each is software, and software has bugs the mathematics cannot fix. A non-constant-time operation leaks a key through timing, a starved random-number generator repeats a value it should never repeat, a parser mishandles a crafted packet, and one bug is enough to hand over everything the tunnel was protecting.

1.1.1 Implementation Flaws [OR]

    1.1.3.1 Non-constant-time crypto operations
        • Timing attacks on RSA-CRT implementation (Brumley and Boneh)
        • Cache-timing attacks on AES T-table implementations
        • Branch prediction attacks on elliptic curve point multiplication
        • Memory access pattern leaks in modular exponentiation

    1.1.3.2 Random number generator weaknesses
        • Predictable seeding from a crippled entropy pool (CVE-2008-0166)
        • Entropy starvation in virtualised environments
        • RNG backdoors or predictable seeding
        • Fork() process duplication causing RNG state duplication

    1.1.3.3 Side-channel attacks (timing, power analysis)
        • Power analysis attacks on hardware crypto accelerators
        • Electromagnetic emanation analysis from network devices
        • Acoustic cryptanalysis of hardware security modules
        • Thermal imaging attacks on cryptographic operations

    1.1.3.4 Memory corruption in crypto libraries
        • Integer overflows in message processing
        • Use-after-free in IKE SA state handling
        • Heap corruption in certificate validation

Past the maths, not through it¶

• Constant-time code is often traded away for speed, and the timing that remains leaks key material.

• Virtual and cloud hosts struggle for entropy, so their random-number generators produce values an attacker can predict or catch repeating.

• Side-channel attacks (timing, cache, power) need proximity, not a network breach, and read secrets a firewall never sees.

• Cryptographic libraries run to millions of lines, and at that size memory-corruption bugs are a question of when, not if.

• Optimisations lean on specific hardware behaviour that can itself be manipulated.

• Old code paths kept for compatibility carry old, exploitable flaws.