DOS ain't dead

speedsys.exe packed (Users)

posted by RayeR , CZ, 15.04.2025, 06:43
(edited by RayeR on 15.04.2025, 06:57)

> I did try to hack 55h to "UPX!" and then adjusted the checksum at offset
> 6Fh and it seems to depack using upx-ucl -d. I didn't run the
> resulting executable but it seems fine. So maybe it is packed the same way
> after all, just different garbage in the hacked fields?

OK, as we have sources now, no need to mess with binary anyway. Sometimes I saw that someone "obfuscated" his binary by overwriting UPX signature. So I just commented out
rem speedin1.exe
in SPEEDSYS.BAT to leave it as is. Now recompiled with TASM 4.1 and made dirty hotfix that allows run on 486DLC/SLC... Also corrected a typo "faind" -> "find" in srcs.

---
DOS gives me freedom to unlimited HW access.

Complete thread:

• debugxv - how to use I/O watchpoint? - RayeR, 08.04.2025, 10:44 (Users)
  • debugxv - how to use I/O watchpoint? - Japheth, 08.04.2025, 12:30
    • debugxv - how to use I/O watchpoint? - RayeR, 08.04.2025, 14:11
      • debugxv - how to use I/O watchpoint? - Japheth, 09.04.2025, 05:53
        • debugxv - how to use I/O watchpoint? - RayeR, 09.04.2025, 11:19
          • debugxv - how to use I/O watchpoint? - Japheth, 09.04.2025, 16:33
            • debugxv - how to use I/O watchpoint? - RayeR, 09.04.2025, 20:08
            • debugxv - how to use I/O watchpoint? - RayeR, 11.04.2025, 06:14
              • debugxv - how to use I/O watchpoint? - Japheth, 11.04.2025, 09:10
                • debugxv - how to use I/O watchpoint? - RayeR, 12.04.2025, 05:59
                  • debugxv - how to use I/O watchpoint? - Japheth, 12.04.2025, 09:16
                    • debugxv - how to use I/O watchpoint? - RayeR, 12.04.2025, 15:02
                  • debugxv - how to use I/O watchpoint? - Japheth, 12.04.2025, 16:58
                  • debugxv - how to use I/O watchpoint? - rr, 12.04.2025, 18:10
                    • debugxv - how to use I/O watchpoint? - rr, 12.04.2025, 19:05
                      • debugxv - how to use I/O watchpoint? - rr, 12.04.2025, 20:11
                    • debugxv - how to use I/O watchpoint? - RayeR, 13.04.2025, 07:12
                      • debugxv - how to use I/O watchpoint? - ecm, 13.04.2025, 14:13
                        • speedsys.exe packed - ecm, 13.04.2025, 14:25
                          • speedsys.exe packed - ecm, 13.04.2025, 14:32
                            • speedsys.exe packed - RayeR, 15.04.2025, 06:43
        • debugxv - how to use I/O watchpoint? - tom, 09.04.2025, 21:06
          • debugxv - how to use I/O watchpoint? - Japheth, 10.04.2025, 13:14
            • debugxv - how to use I/O watchpoint? - tom, 10.04.2025, 18:27
    • debugxv - how to use I/O watchpoint? - RayeR, 09.04.2025, 02:58
      • debugxv - how to use I/O watchpoint? - Japheth, 09.04.2025, 05:50