If you suspect that your BIOS is infected (BadBIOS?), I could only suggest doing a hardware ISP flashing with one of the flashrom-supported programmers (i.e. green PCB ch341a) and a test clip like SOIC8 (to be able to attach to a chip without any soldering) while the board is turned off of course. This should be the most reliable. Before flashing a new known good BIOS image that you might obtain i.e. by extracting from a manufacturer's update utility, please dump the previous contents with a programmer: so that you'll be able to recover from it just in case, and maybe even look through it for any hard evidence of a BIOS virus to share it with the community (if that's really true, could be quite interesting for research purposes). Also I copy this message to a flashrom mailing list, in case someone else could also advise you.
On Wed, Apr 7, 2021 at 2:05 PM Rahngue NGARIERA youetonam@gmail.com wrote:
Hi Mike. I didn't mention it in my previous email, but I used also flashrom 0.9.6 on Ubuntu 14.4 Which failed on both Probe and Read with "Hardware sequencing was requested but the flash descriptor is not valid. Aborting". While using version 0.9.4 (on DOS) I did both Probe and Read. As You said, the 2 chips FlashRom 0.9.4 found (AT25DF081A and AT26DF081A) are the same and one chip. And checking on the main board I did see that chip. It's AT26DF081A. I did try to read on FlashRom 0.9.4 (on DOS) using the -c parameter with AT26DF081A first (as in -c AT26DF081A) but that failed. Then just to see, I tried to read with -c AT25DF081A ( since 0.9.4 was seeing two chips). But it also failed. I'm sending you again the Probe log and the Read logs using FlashRom 0.9.4 : READ1.TXT (AT25DF081A)
and READ2.TXT (AT26DF081A).FlashRom 0.9.6 (Ubuntu14.4) and FlashRom 1.2 (on DOS) both failed whether reading or probing even with -c AT26DF081A ( -c AT25DF081A) with the same message at the end saying that flash descriptor is invalid. This Dell system I want to read from, I think, has its bios infected. When It comes to bios, I prefer to operate from DOS: I think it's safer and maybe help avoid any action from the virus. Please Mike, what do I do for FlashRom to successfully read this chip? I need to confirm if this bios chip is infected. Thanks for your help, Etonam.