A potentially exploitable out of bounds write vulnerability in vt100.c was found.

Vulnerable code:

static void (*vt_keyb)(int, int);/* Gets called for NORMAL/APPL switch. */
static void (*termout)(const char *, int);/* Gets called to output a string. */

static int escparms[8];         /* Cumulated escape sequence. */
static int ptr;                 /* Index into escparms array. */
static long vt_tabs[5];         /* Tab stops for max. 32*5 = 160 columns. */

//...

  /* See if a number follows */
  if (c >= '0' && c <= '9') {
    escparms[ptr] = 10*escparms[ptr] + c - '0';
    return;
  }
  /* Separation between numbers ? */
  if (c == ';') {
    if (ptr < 15)
      ptr++;
    return;
  }

With crafted input, attacker can write out of bounds of escparms array and could potentially overwrite ptr pointer.