I can confirm that both VMs are using /bin/gunzip and have the same checksum.
$ which gunzip /bin/gunzip $ sha512sum /bin/gunzip 483beae8cd211cff3bfa056bf573f0f0fa068eb0872924da9d01537232fa815d7bfd817bfb411fea65f20ae71e204256e0cc0255b06c1363fd4f80d918b2d76c /bin/gunzip I tried with a smaller file 'kernel_headers.gz' and I cannot recreate the bug. The extraction works on VM #1 and VM #2, the file is 87M compressed and 383M uncompressed. The original file that causes the CRC error is 1531M uncompressed and 344M compressed. I also started a new VM (#3) in the same EC2 zone, same AMI/Type, same checksum of /bin/gunzip, and tried expanding the original file ('kernel.h.gz' with the same sha512sum). It works. I was attempting to exclude the CPU as a factor and though it has the same CPU, the flags listed are different: processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 26 model name : Intel(R) Xeon(R) CPU X5550 @ 2.67GHz stepping : 5 microcode : 0x11 cpu MHz : 2666.760 cache size : 8192 KB physical id : 0 siblings : 2 core id : 0 cpu cores : 1 apicid : 0 initial apicid : 2 fpu : yes fpu_exception : yes cpuid level : 11 wp : yes flags : fpu de tsc msr pae cx8 sep cmov pat clflush mmx fxsr sse sse2 ss ht syscall nx lm constant_tsc rep_good nopl nonstop_tsc pni ssse3 cx16 sse4_1 sse4_2 popcnt hypervisor lahf_lm dtherm bogomips : 5333.52 clflush size : 64 cache_alignment : 64 address sizes : 40 bits physical, 48 bits virtual power management: -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1131982 Title: CRC error To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gzip/+bug/1131982/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs